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SD card not showing files when connected to pc
When my phone MOTOROLA G3(2015) is updated to Marshmallow, its not showing files when connected to PC. While connecting, it shows options as charing only, PTP, MTP, MIDI. When I select MTP, it shows the external card, but not showing the contents, where as internal memory is detected and all files are shown.

This is a well discussed and easy to fix bug... Disconnect USB cable, go to Settings, Apps, and Show System Apps and find External Storage and Media Storage and clear data and cache on each one and reboot, then give it 5 min after full boot up to rebuild media databases and connect to USB and select MTP. Should be good to go.
EDIT: In some instances where the SD card contains a large number of (media) files, it can take more than 5 minutes for the databases to rebuild. There is no way to see if the status of this database buildup in the phone itself, so sometimes you just have to be patient.
Also note that some users have stated that this is not sufficient by itself, but sometimes the system cache partition needs to be wiped and rebuilt. Official instructions for performing this operation from Moto are here. Note that this operation can take significant time... 5-15 minutes, occasionally even longer, do not interrupt the operation.

I convert the sd card (16GB) as an internal storage but now when I connect to computer, it only show internal storage (8GB). How can I copy thing to my "sd card" from computer?

@truongnm This comment is not directly in regards to this question or answer. If you have a different question, please ask it in a separate question including all relevant details. This is not a discussion forum.

I have done all this, still its showing only external card. When connected to ubuntu,  it shows external card and contents. Problem is with windows, i have installed the usb drivers, updated and troubleshooted it. Still nothing happens..

@SajinShereef If it's working in Ubuntu, you know the phone is working properly... I'm not sure I can help you too much with Windows, but it doesn't require special drivers to use MPT, they are inherent in the OS.

Ya phone is working properly. The problem is just with the windows I think, anyway thanks for the support

I had to reboot my phone 2 times after clearing data and cache to fix this issue.

Some people have noted that after this procedure, access is still not possible until the system cache partition is wiped and rebuilt. I will edit my answer accordingly.

I deleted cache and data for both "External Storage" ("Archivio esterno" in Italian) and "Media Storage" ("Archivio contenuti" in Italian) apps.
Turned off the phone.
Turned it on again.
Changed from USB recharge mode to MTP, then back to USB recharge mode, then back to MTP.
Still same problem, SD card content is not showing up... :(
UPDATE: after several minutes, content is finally showing up!!!!

Confirmed to be working on LG G3 6.0 containing 32GB SanDisk SD card filled with 17.85 GB of data, and waiting of 20 minutes right after rebooting.

This worked for me on my OnePlus One - with the MTP protocol. Will it ever be fixed?

After about 4 hours of installing drivers, wiping data & cache of apps, wiping cache partition, etc...
I found the solution was just to change USB option from 'MTP' to Charging while USB was connected to the computer, then while still connected, change the USB option back to MTP once more, voila!
Edit: How to find the USB options may vary between devices. On Samsung Galaxy devices, touch and drag the notification bar down, then tap "Connected as a <whatever-device-type-the-phone-is-currently-connected-as>".

Where is this setting, pray tell? :-/

After an update from motorola, it works..

Could you give some more details to help other visitors with the same problem? If you could [edit] your answer to give the build number that works for you, that would let people tell if updating should fix it for them.


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adb pushed file not showing over MTP
I want to copy a file ~5G to my Oneplus One(running cm-12.1-20151117-SNAPSHOT-YOG7DAO1K6) over MTP, but it fails at finishing copying. The copied file is 0KB so I delete it. Later I successfully copy the file over adb but I can't see the file over MTP when the phone is booted. I can only see the file over MTP when the phone is in twrp recovery.
There are some similar questions on this site but the answers don't work.
What I have tried:

Clear data on the Media Storage application and reboot. Doesn't help.
adb shell am broadcast -a android.intent.action.MEDIA_MOUNTED -d file:///sdcard. Doesn't help too. What's worse is that now I see even less files over MTP. I can only see all the files over MTP when the phone is in recovery.
Settings → Developer options → Development tools → Media Provider → Scan SD Card. Doesn't help.

[edit] Deleting that large file and rescaning SD card makes all the files visible again over MTP. With that file on my phone, scanning SD card never finishes. For now I can only avoid saving large video files on the phone due to this glitch.

MTP sucks (at least for me), so I once looked for alternative solutions and  came up with this post: Is there a viable alternative to MTP for file transfer? They may look odd at first  but they are easy to follow in daily use.

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


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How do i root Android x86_64?
I installed android x86_64 and now I want to root it but all the root scripts are for 32-bit versions of Android.
I am using console os lollipop that is not rooted.
What are my options?
Thanks

Exactly which Android version are you using? I don't see any 5.0 based image here: http://www.android-x86.org/download

Additionally, on which device?

If you are using an x86_64 build from http://www.android-x86.org/download, such as android-x86_64-5.1-rc1.img, it is already rooted.  There's no need to run a root script.
If that's not where you're getting your image from, please update your answer to add that important detail.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


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Bulk Android Device Provisioning
I'm working for a company that wants to hand out 1000's of Android tablets with a bunch of OS customisations, i.e. specific preinstalled apps, default home page, amongst other things.
What solutions are available to achieve this (without having to go through each device manually)?
Ideally, if there were a mechanism to create an Android OS image that could be deployed to all devices during manufacturing process, that'd be perfect.
Edit: I'm not looking for a MDM solution for enterprise, just a one hit preinstall of apps/settings during device manufacturing/setup.

Possible duplicate of Set up and install non play store apps to multiple devices?

This sounds like something you'd need to talk to the manufacturer about.

Related: how to do bulk updates across multiple devices / Can I set up one android phone, create a backup and restore it in multiple phones? / Centrally managing large number of android tablets / centrally manage corporate android devices / Best Practise for deploying a 'clone' image across 200 android tablets

I don't think this is a duplicate of the suggested question. A one-off run of several thousand devices has completely different needs to setting up a handful each day.

More related: Clone and distribute Android 4 device with preloaded applications / Clone Android Device. Make your pick :) Please check them out and then point out which of them fit or why none of them fit (whichever the result will be).

Thanks for the responses, in the end, the manufacturer of the tablets is providing the customisations at the point of manufacture.


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How to run some admin (Owner) root apps in background for all Users?
I'm using CyanogenMod 12.1 (Rooted)
I want to set up a multi User system with me as the admin. I want all or some of my root apps to run in the background. I don't want the root apps to be shown to the normal user if posssible.
Note: I need to run some apps in the background for datalogging and security, and scanning purposes. For Example I want to run a Linux Distro and some other apps that run Python Scripts. I figured this feature might be available cos it is in Windows PC and Linux. These apps autostart without user inetraction in the admin account. They have a GUI however.
If this is not possible then please suggest me alternate ways like locking or hiding the apps.
Is this possible at all or does the User isolation system make it hard or impossible.
Any workarounds will be OK too.
Thanks.

Your query seems unclear to me. If you're setting multi-user system, then other users wouldn't be able to see the apps  installed in your user account (user ID 0). What's the problem then? Why do you want to hide apps now? (Note that an app cannot be forcefully run in background.)

Please comment on why this is downvoted? I made sure it wasn't a duplicate.

@Firelord I actually want to run some python scripts and some other services in the background of other users. If this is not possible I'd like to know about the workardound. One of the main conditions however is that other users should not get root.

@Firelord So in Android or CM User system the apps are completely isolated and Admin or Owner can't make processes run on the other user accounts? Unlike in Linux and Windows desktops?

I don't know what you mean by "for all users", but what you're describing is just how apps work on a multi-user system. Say you have two users A and B on a tablet. A unlocks the lock screen and starts an app, which has a service which runs in the background to do something. Now A locks the screen again: his app is still running in the background. Now B comes along and unlocks the lock screen into his home screen. A's app can keep running in the background, completely separated from whatever B is doing on the screen.
The only interaction between A's background app and what B is doing is if B uses enough system resources to cause Android to start shutting down background processes to. This acts much the same way as a background app on a single-user system: if the system needs to reclaim resources, it'll stop those background services and reclaim their processes first.
So it doesn't matter if you're the owner user, or if the app in question has root privileges: your app can run in the background just the same, regardless of whether you're using the screen or somebody else is.

Interesting! So there is neither control nor security. For example I switch users to connect to Tor or a VPN and keep accounts seperated. The other user apps will still be accessing the internet and sending all the data they want probably through the VPN session I setup or directly. Either way is bad.

What about the processes of programs that always run in the background. Like Daemons. Like System Apps. I mean apps like SuperSu with deep integration and are never shut off. Will such processes keep running?

BTW I am not talking about online accounts. I'm talking about System Users that seems to create a new empy page without all the other users apps installed. Also there is no sign of other users apps running.

@Wally System apps can choose whether to spawn another instance or not for each user.  They could also choose to shut down when users are changed.  I've written code doing multiple variations of this before.


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How to detect if an apk is from the Play Store or Sideloaded?
I understand that apps are signed by both Google and the developer.
How do I detect if an apk is from the Play Store or if it is sideloaded.
I'd prefer if the method worked on all major platform only if possible including Android itself.
Even if sideloaded I'd like to know the source of the app. Like is it from Play Store.
I'm thinking of using an app or method that uses signature detection.

Signature detection doesn't help much to detect how an app was installed. But there's the "installerPackageName" property which tells you that when using adb dumpsys package (it carries the package name of the app having installed it, which would be the playstore's when that was used, or F-Droids, etc., or "unknown source" when completely side-loaded.

@Izzy I'm more concerned with dealing with the apk itself. If you use an apk grabber or adb it is irrelevant wether the apk is sideloaded. I want verification that it is from Play store.

You cannot tell if the .apk originally came from Playstore – but you can tell whether it matches the one available at Playstore. Here's what you need:

the .apk in question
the .apk of the same app in the same version from Playstore
openssl

Unzip both .apk (each into its own directory), and compare their certificates (stored in the META-INF/ directory. Details on a thorough comparision can e.g. be found here. The command you'd need is:
openssl pkcs7 -inform DER -in META-INF/CERT.RSA -noout -print_certs -text

Alternatively, if you haven't openssl installed but the Oracle JDK:
keytool -printcert -file META-INF/CERT.RSA

or
jarsigner -verify -certs -verbose ../Example.apk

If the certificates match, both APK files where signed using the same key. Unless the dev's key got compromised, that should mean the potentially sideloaded APK should be fine (no guarantees the dev himself didn't play games – but if size and MD5 of the APK also match, I'd say it's safe).

While the part about comparing the signature in the META-INF is useful, the only way to be sure that an APK is the same as the Play Store's, is to compare their MD5 checksums, as you said. In fact, the tool named apktool contains an alpha setting to try and recompile an APK, and retaining the original signature in the process, so checking only the RSA may prove to be unreliable in the future.

@DeathMaskSalesman that's why I used that "conjunctivitis" (should..should). Another point is: an MD5 mismatch must not necessarily point to a compromised key. Some devs have their apps in different variants carrying the same version number (think e.g. of Tasker): due to restrictions in Playstore, they offer a "full fledged version" (with options Playstore would reject) via a different channel.

Correct. So, the only way to be almost sure would be to check both signature and checksum, as you already said.


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Apps can't connect to internet
I have a connection problem with any app on Android 2.3.5. I can access the internet with the stock browser but any other app with full network permissions isn't able to connect to the internet. My handset is a Simvalley SPX-5.
Any ideas?

How you are connected (wifi, mobile)? Please also take a look at the answers to I rooted my phone. Now apps cannot connect to the internet but browsers work fine. Moreover, I remember we had similar questions already a lot, so you could possibly find an answer there -- just follow the tag-links below your question.

Did the answer help solve you issue? If not, what is missing?

I couldn´t try it until now. I´ll write back, when I´ve tested the reset.

You can try one of these steps to solve it.

Is the problem recently? Have you ever used the phone when this all worked? Maybe then you can try to reset your phone. By setting your phone to the factory settings maybe some kind of glitch will be solved.
If you've never used other applications on the internet before, and you are using the phone for some time now. Maybe you can try to contact the manufacturer of your device. They can maybe help you better. Because I think, in that case, there is probably something wrong with your phone.

PS: Are you sure you are correctly connected to the web? Maybe if you are using a cellular network, it can be very slow.. Also check this link.


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ADB 'su: permission denied' in recovery mode on rooted device
ADB 'su' command returns 'su: permission denied' on a fully rooted device in recovery mode. I can modify folders and files that require root access on phone (when it's booted). ADB also works when it's booted - I only need to confirm a superuser pop-up on the phone.
USB debugging is enabled.
What can the problem be?
Thanks!

What device are you referring to?

What is the exact command you are using? You should be able to 'adb shell' into the phone and once inside, simply run 'su'.

Most recoveries don't work in root mode - and root mode cannot be acheived, as the SU binary calls your superuser app to gain permission to use root mode.
As the su binary cannot call the app, it stops you using SU mode.
It could also be due to the fact that the su file used in recovery is the stock su file found in Android, and this doesn't let you switch to the root user (as if it did every device would be rooted).
Some recoveries allow root to be used - you will have to search for one for your device.

You are not going to get a popup superuser confirmation from within a rooted recovery.
That popup superuser confirm dialog only happens in a fully booted normal Android environment.
Sounds more likely that the ramdisk used within the recovery, has the setting ro.secure=1 in default.prop by accident thus preventing the su binary from getting executed with a error su: permission denied.
Had it being set as ro.secure=0 then adb would allow the s witch u ser to root function as normal.
OP: Please give more details such as make of handset, what version of recovery, is it clockworkmod or stock?


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g-mail app: download without an attachment
I have a Samsung Galaxy S2. I use GMail, and I am using the GMail app on this phone.
Is there a way to have emails downloaded to my phone without the attachments?  So when I open the email I have the option to download the attachment, if I chose to? If not: is there another email client/app you would recommend?

I have an SGS2 too. The GMail app never downloads your attachments automatically. You'll see a list of the attachments at the bottom of the email, with the option to download them. The attachments get downloaded (and the corresponding bandwidth used) only when you press download. You can already safely read the email without worrying about GMail using up your bandwidth.

thanks.  I did not realize that the attachements were not really downloaded till you open them.  issue resolved

I don't know about the GMail app (as I rarely use it). But for my normal mail via IMAP I use K-9 Mail, which lets me configure the size limit per mail to download (defaulting to 25kB AFAIR). Attachments are only loaded when you hit the button to tell the app you want it. You can also read your GMail mails with K-9, so both parts of your question are covered.


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software does not want to update
I have a Samsung Galaxy S3.
Every time I try to update my software/ check for updates I receive the following message: "failed to update firmware due to network or server problem. Try software update via settings>software update> Update, or try using PC Kies later"
I have tried everything but it still gives me the same messages.
sometimes I don't even try to update my software and I will receive the same message out of the blue.
Can someone please help me?

That is dependant on your carrier and country you are based in. Alternative would be to use multiloader and download the latest firmware from samfirmware, this requires user registration to download the latest.. :)


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continuous booting of PIPO M2
What do I do? My PIPO M2 has been booting continuously for 3 days. I have tried to switch on and off overtime but still not coming up.
Please help me out, I feel like throwing  the pad away.
Kindly treat.
Thank you.

Give more details on what you did exactly for the tablet to end up boot-looping? Were you flashing a ROM onto it? Did something incorrectly? Details please? :)

Yes, more information is needed. It sounds like it is in a boot loop. If you flashed a custom rom, then you need to wipe the /data and /cache. If you did something else, like delete "system" apps, you may need to reflash a stock rom. And based on your tag, it sounds like you flashed a different ROM.


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Samsung Captivate not booting after root
I recently installed Clockwork Recovery, and used that to install CyanogenMod 10 on my Captivate using this guide. Every thing worked perfectly.
I backed up the stock ROM. Then I realized that my contacts and data were gone in the new ROM. I read in an article that you could restore the data part of the backup using the recovery in Nandroid, so I recovered it. But when I rebooted, the phone got stuck at the spinning CyaogenMod screen.
I made the problem worse by trying to flash the mtkareys zImage kernel, and repeated the process described in the guide. Now, I can't get into recovery mode nor the Android (CyaogenMod) OS.
I suspect that I would need to use some tool that uses my Ubuntu 12.04 or Windows 7 PC, because the only resource that I have access to is download mode in the phone. Nothing else seems to work. Please understand that I am a beginner who has never even written an app for android (I do have the sdk installed though).

Why did you flash a kernel mtkareys zImage kernel to quote OP, when really you wanted to restore the data part of it...? What was the deciding factor in that?!

What Izzy said is correct. Also, never give up! I found that there is always something you can do to unbrick your captivate.
The xda-developers wiki page is very useful in this regard. The sections about bricking and unbricking should be very useful. While it's very difficult to enumerate all possible ways of unbricking here, understanding the nature of the brick (soft or hard) and looking for alternative ways in the forums is always helpful. The techniques that I know of so far are:

The 3-button method and its variations, as listed in the wiki page above. (There are variations, just search for them in xda-developers)
Using your PC and the USB cable. Izzy's answer is one such method.
Hardware solutions that involve cutting a USB cable or using resistors. When you have a hard brick, you may have to resort to these.

Good luck and don't stop searching! There is always a way to unbrick your Captivate.

rather than just adding a link, please explain what the method is, with a summery of the article you have linked.

Thank you for your tip on how to write a more helpful answer. Unfortunately I do not have time to write a summary and I believe the information that I gave can be useful as is.

Turns out I do have time now. Hope this is better. I need 10 reputation so I can provide a better answer to this poor fellow.

That's a stack of errors occuring to you. Before I present you a possible solution, let me point out what your mistakes have been -- to avoid those in the future:

Never ever go to restore system data (this includes SMS, contacts, and other data from system apps) from a Nandroid backup of one ROM to a different ROM. This might work in some cases (when those ROMs involved are very compatible), but most likely will bring you in trouble as it was in your case. Apps store their data mostly in SQLite files, which contain databases -- and the structure of those databases very often differs. So you break those apps, which leads to different kind of trouble -- up to the point of boot-loops or incomplete boots, being stuck at the logo. This is also why Liam is correct that a "data wipe" (or "factory reset") would have solved the issue (as it would remove those broken SQLite files, and the apps would re-create them emptily).
If you really need to transfer data of system apps between different ROMs, the best way is to export this data before you flash (contacts can be exported directly from the contacts app, and would then be stored as .vcf file on your sdcard; for other things like SMS there are apps available on the playstore), and import them afterwards. Also, as you are rooted, you should consider buying the pro version of Titanium Backup for a complete backup (in addition to your Nandroid backup). Titanium Backup includes a "Migration feature" which should work for those kind of data as well.
Never flash a kernel if you are not 100% sure it works for your combination of device and ROM. If you break things here, you device won't be able to boot in normal or recovery mode, as you experienced. Especially do no such thing if your device already has other trouble -- first solve that trouble before doing such "deep system changes".

Now, you are 100% correct: As you are no longer able to boot into recovery mode, you need a helper tool "from outside". For Samsung devices, this tool is either Odin (which is what Samsung itself provides), or Heimdall, which is a cross-plattform alternative to Odin which will also run on your Ubuntu PC (Odin will not, as it IMHO is for Windows only). Use either of the two to flash any ROM compatible to your device, so you get your recovery mode working again. Once that is done, you might start over flashing ClockworkMod recovery, then restoring your complete Nandroid backup, exporting your data as described above, and finally switch to the ROM you wanted to use.

Good luck! If that fails, give Heimdall a try. I don't own any Samsung device, but I've read quite often that Heimdall is to be preferred over Odin. The Whys and Hows for that are better explained by a Samsung user who can tell it first-hand, though ;)

If you had recovery, a simple data wipe would have fixed the boot loop issue. The issue you are describing sounds like a kernel/system issue.
The only fix would be to try and flash a new kernel via download mode - you would have to find a program that could do this.
If this isn't possible (it may not be), then you should consider your phone bricked, and you should take it to your nearest service center for repair (don't tell them you rooted it, just say it wouldn't turn on after you had turned it off).


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HTC XE turned itself off and won't turn back on
I charged my phone overnight for at least 6 hours. It was working fine when I checked my emails first thing this morning.
Then, the phone restarted itself (not uncommon!). Since then, I can't turn it on. I have taken the battery out and left it out for around 2 hours; it still won't turn on.
I have tried to turn it on in recovery  (holding the down volume button and the power on button) and still nothing happens.
Any help would be greatly appreciated.
Nick

Have you tried holding the button down? When the phone is running, a single quick press on the power button will usually wake it up. When it is completely off, like due to the battery being removed, you often have to hold the button down for a short while.
You should also make sure it is charged using a wall charger. A completely depleted phone may not be able to charge from the USB port of a laptop.
Beyond that, I have seen cases where the power button wore out.


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Removing second SIM signal sign from notification
I have karbonn a9 plus smart phone. It is a dual sim phone, but I only use 1 SIM.
The second SIM signal icon with no network always shows in the notification area. I want to remove it from my notification area.
How do I do this? I have rooted my phone.

Root your phone. Install Xposed Framework and install a module for hiding the extra sim sign.

OP stated that their phone is already rooted...

Xposed sounds like a good approach here. But which module are you referring to? A link would be helpful. Meanwhile, there are plenty of Xposed modules around, your question comes close to "install some app from Play" without telling which one to chose :)


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Insufficient memory to download apps from playstore?
I have rooted my device. I am not sure if this is connected or not, but I cannot download apps from the play store: I get a message stating that there is insufficient memory. I have 5.6 GB available on device and 32gb available on the SD Card.
My device is a Galaxy Note 2.

We get this question frequently here, so please check: Why am I getting a “Low on Space” warning and having other weird problems?, HTC Desire low on internal storage, How can I deal with “Low on Space” messages on my HTC Incredible?, “Cannot download, not enough space” when “Phone Storage” clearly lists enough space

Btw: It's the internal storage (phone storage, nod sdcard) causing this issue. Here you need at least 25 MB free space.


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Plugged a Bluetooth USB to Tablet but seems not working
I have insert a USB Bluetooth dongle to a Tablet via the USB port and try to turn on the Bluetooth in the Android but fail.
So, how do one know if the USB Bluetooth dongle can be supported for a tablet that have a USB port? (Given that the USB Bluetooth dongle have been tested to work fine in a desktop PC and there is no further information on the tablet manual on which Bluetooth dongle is supported for the tablet.)
The Ice-cream tablet was not rooted yet.
Is there some kind of Android Apps that can check or verify the above scenario?

Most tablets that comes with the Bluetooth share app installed, and have a Bluetooth option in Settings, while not having a built-in bluetooth, typically indicates support for such dongles.
I have used generic Android TV Box (CDR-King brand) with no bluetooth built-in but has a menu for it. Plugging a bluetooth dongle to a usb port activated it. Based on this, your tablet's ROM does not support bluetooth. My advice is to root it, and flash a custom ROM with bluetooth support if applicable.

I kind of suspect is that the tablet firmware that might be the culprit.

but is the bluetooth dongle plug n play (no additional drivers needed) to use? Most branded bluetooth dongle require drivers to run on pc, while generic types (one I use on the TV box) generally use the built-in bluetooth drivers. Does your tablet also comes with a bluetooth toggle?


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Display a portrait-mode app on a horizontal rotatable screen
I need to display a portrait-mode app from my Samsung Galaxy S9 on a horizontal PC screen. The PC screen is able to rotate to portrait mode, but the problem is that the image rotates with it. The image is always displayed horizontally in regards to the PC screen. This means that when the PC screen is horizontal, the image is displayed in portrait mode in the middle of the screen, covering only a small "pillar".

When I rotate the PC screen to portrait mode, the image rotates with it, leaving the same "pillar" covered (though now rotated 90°).

What I need is for the image to be displayed in portrait mode while the screen is in portrait mode (meaning the image is rotated -90° when the screen is horizontal, making it utilize the entirety of the screen).
I've contacted Samsung, and they say there are no settings on the phone that allows me to do this, so I'm looking for an alternative solution, such as an app or other third-party clients. I've also read somewhere that I have to root my phone (and change some codes?) in order to achieve this, but that seems way too advanced for me. Alternatively, I could use my old Huawei P9, if that helps.

A quick Google suggests the use of an app like ‘Rotation | Orientation Manager’ by Pranav Pandey from the Google Play Store.  This app supposedly allows a user to override the sensor/UI of the given tablet/Android phone.  I will keep looking to see if there's a way to do it without an app if you like...

Using Miracast or an HDMI cable, the content will always be displayed as it is on your smartphone > I suggest trying this app on your phone to rotate the image and then adjust the image on your monitor as per your needs.
Rotation Control
Activate Guard Mode (shield icon) and choose the desired angle.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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Galaxy S7 - How to back up stored email mailboxes with ADB?
I've been through several threads on Stack Exchange / XDA to find a solution that yet eludes me for the following task :
As we all know, when we create an email account with our Android device and use the default email app, in my case Samsung Email, the synchronized emails are stored on our phone, in my case (rooted Samsung Galaxy S7 edge - Android 7.0), in this location: /data/data/com.samsung.android.email.provider/ with folders : App Cache App Databases
The idea, from what I have read, is to back up all those folders and the databases stored within them with ADB and then use SQLite tools to convert the databases into usable/readable information.
The problems I have encountered until now:

when I use ADB backup function, the stored backup is less than 1kb size, meaning the backup didn't work, this can be the result of the wrong app name or no Allow_Backup Flag on that app (system app)
I have used several tools to get the exact name of the app, in my case com.samsung.android.email.provider or com.samsung.android.email.provider-1 but still no result
I have tried to use the backup -all command, and that's how I realized some apps were not backed up in the resulting file, including the email app for my device.
I have read that in order to backup an app, it needs to have the ALLOW_BACKUP flag, and the app (system app) does not have that flag

What do you think? what should I do from here?
(Important: the idea is to extract/backup the whole mailboxes and be able to access the contents of these mailboxes on a Windows/Mac mail client. I have no use for the 'export email to file (.eml)' available in the Samsung app, as that would require to do it for each email one by one).
Sources:

Android email Extraction
How to backup with ADB
Backup problems
Backup FLAG info
SQLite database use

Why don't you copy those files & folders to another folder of your choice, then use sqlite to open the databases?

What you want to do is simply impossible. The app Samsung Email (com.samsung.android.email.provider) contains the entry android:allowBackup="false" in its AndroidManifest.xml.
This entry totally disables ADB backup for all of its app data. Whatever you do, the adb backup will therefore never contain the email data.
If the app has no integrated bulk backup/export function for the whole mailbox, you can not gain access to its app data unless you have a rooted device or you use a root exploit.

Please view Source N_1 = it can be done. If not done that way, maybe the solutions are : 1- Edit the app flag to allow Backup. I know this can be done in general, but can it be done with system apps ? Since Samsung Email is not a default android app, maybe this can be done? 2- work with the files in Cache and Database and reverse / decode them (reverse java) back to emails ?

@At0mX The article is 4 years old. May be at that time Samsung Mail did not not yet had the allowBackup="false" entry. According to the versions available on apkpure.com Samsung Mail from 2017 already had this entry.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
Is TrimApp specific for Samsung phones or present on all 4.x Android Phones?
I'm confused regarding the Trim Video application. On my Galaxy Note it can be launched from the Gallery when I play a video and chose Trim from the menu.
I would like to know if this Trim application is available on all the Android 4.x phones or only specific to Samsung?

Can you edit to include the source of where the app came from?

It comes with my Samsung Galaxy Note, I haven't installed it from any external source. I would like to know if the same comes with non-Samsung 4.x phones.

There are a couple of video trimmers in the playstore in case you need one on another device.

No, I just would like to know if a stock Android 4.x firmware comes with any vdeo trimmer. Unfortunately I only have 2 Samsung devices, don't have anything else.

More than likely, the Trim Video application is part of the Samsung Galaxy Note ROM, so its proprietary and confined to Samsung only. :)

@t0mm13b I guess that's the answer then, I can accept it then if you put it as the answer.

There's certainly no such app on my Samsung Galaxy Nexus.

@Alex - Trim video is also present on my Galaxy S3 on 4.1 JB.


text:
SD Card Multiple partitions USB access
I want to split my SD cart in 2 partitions: one for android, and one containing a bootable OS used from computers through USB or by inserting in card readers. I can't access the second partition from USB!
Specs:

Phone: motorola defy+
System: CynogenMod 10 (android 4.1.2)
SD Card layout:

Primary FAT32, 1Gb, intended for android only (apps data)
Primary EXT4, 15Gb, invisible from android intended for computers (bootable linux system)

Current status:

Everything works with a laptop SD card reader: I can mount and browse both FAT32 and EXT4 partiations. I can boot from the SD card and boot to the linux I installed on the ext partition.
From the phone: android can mount and access the FAT32 partition, the ext4 partition is invisible just like I want.
Problem from USB: When accessing the card in the phone from a computer through USB (android is configured as USB mass storage device), I can only access the FAT32 partition.

My question:
Android seems to be exposing only the first partition as a block device through USB. Therefore I can't access the second partition, or even see it with partitioning tools. Obviously, booting from it also doesn't work.
Can I make Android to expose the full SD card as a block device through USB, so that all partitions are visible from a computer and I can boot on it.
Any help or pointers appreciated, thanks!

Your guess is correct: only the first partition is exposed via UMS. This fact is used e.g. by some advanced App2SD+ stuff (and e.g. Link2SD) so "moved apps" and their widgets are not broken when USB is connected. I'm afraid the answer to your question will be a simple "No".

You can try to use the MBRFAT hack — the first sector which looks both like a FAT boot sector and a MBR partition table.  Such images can be created by the makebootfat utility.
I did not try to do this actually, but in theory you should do the following:

Create a files directory which should contain files to be placed into the FAT32 filesystem image (it could just be empty).
Locate the following files:

mbrfat.bin — should be contained in the makebootfat package;
ldlinux.sys and ldlinux.bss — come from the Syslinux 3.x package (use a 3.x version, I'm not sure that makebootfat is compatible with more recent versions).

Create a file for the FAT32 filesystem image with the desired size of the FAT32 part:
dd if=/dev/zero of=fat.img bs=1M count=1024

Create the FAT32 filesystem image with MBRFAT:
makebootfat -o fat.img -m mbrfat.bin -b ldlinux.bss  -c ldlinux.sys -F -Y -v files/

(Note that placing ldlinux.sys in the files/ directory does not work — it must be copied with the -c option.)
Put your card in the phone and attach it to your computes as UMS (it you work with a card reader, it would be hard for you to mount nested partitions).
Write the created image to the whole disk device exposed by your phone:
dd if=fat.img of=/dev/sdX bs=1M

Create your additional partitions on the same device that you have written the image to. If you want to place the bootloader on the EXT4 partition instead of using SYSLINUX on the FAT32 partition, mark your EXT4 partition active and remove the active flag from the FAT32 partition.
Make a backup copy of the MBR+FAT sector:
dd if=/dev/sdX of=mbr_fat_backup.bin bs=512 count=1

Install Linux on the EXT4 partition, being very careful to avoid installing the bootloader to the MBR of the disk. Some installers do not support installing the bootloader into the partition boot sectors; in this case either skip the bootloader installation and install it manually later, or (if skipping is also not possible) restore the MBR+FAT sector from the backup after installation, then install the bootloader into the partition boot sector. Or you may configure SYSLINUX on the FAT32 partition as your bootloader (for this you will need to copy the kernel and initramfs image to the FAT32 partition).

This configuration would work as follows:

Android will see the outer partition contents just as a FAT32 partition, although with the number of sectors in the filesystem smaller than the partition size. The Linux kernel on the Android device will not try to parse the nested partition table, therefore the nested EXT4 partition will not be accessible from there.
When Android exposes the partition contents as an USB mass storage device, the OS on the host computer will parse the sector 0 of the exposed device as an MBR partition table, and will see multiple partitions there. For the FAT32 partition it will use another sector as the boot sector containing the FAT32 BPB; this copy of BPB will contain a smaller value in the “number of reserved sectors” field, so that the FAT and data clusters will end up in the same physical sectors as when using the BPB in sector 0 of the outer partition.

The problem with this config is that accessing the EXT4 partition when using the card in a card reader will not be possible, unless you use utilities like kpartx to expose nested partitions. Booting when using a card reader could work if you create another partition on the card directly and install some bootloader there (with a separate copy of kernel and initramfs images); note that this partition will not be accessible when using the phone.
In addition, mbrfat.bin is somewhat buggy, and some computers fail to boot when using it.

You may only be able to do it via it's Recovery by using the Mount USB Storage function. It is present in all custom recoveries. The plausible reason that you cannot access the EXT4 partition in android is because it might be mounted and used by Cyanogenmod. You might be able to forcefully unmount the EXT4 in the Recovery on the Mount menu and unchecking the corresponding mount, if the kernel supports it.

It's no mounted, I think @Izzy is right. I can't even access the partition table through USB. Only the first partition is exposed.


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How to use an external USB keyboard with a Galaxy S II or a Huawei Y201 Pro
The background:
I recently learned about OTG USB cables that can be used to connect peripherals to Android devices. I had this idea of using an android device with a usb barcode reader connected (which basically acts like a keyboard) and an in-house developed app, for stock management in a warehouse.
The first step was to buy the OTG cable. The second was to start testing peripherals connected our existing Android devices.
The problem:
When I connect any USB device to a Huawei Y201 Pro (4.0), there is no feedback from the device. No error, no response from the input, nothing.
When I connect mouse to a Galaxy S II, it recognizes the usb cable, then a cursor appears on screen and all works great. However, when I connect a keyboard (I tried around 5 so far), a notification says that the cable was connected but right after that it says that no devices are connected.
My question:
Is there something I'm missing to make this work?
If not, some secondary follow up questions: What are the things I should look for in making this idea work? Is this connectivity more dependent on the Android device? OS version? Peripheral?

Try plugging a powered USB hub in and then plug the keyboard into that. It may be that the phone does not supply enough power to the keyboard.

Maybe your mobile doesn't support OTG. It may also need to be connected via a powered USB hub in order to provide enough power.

You can try to make your (perhaps incompatible) keyboard work using Externel Keyboard Helper.
If this works here is the fully functional Pro version.
I bought this app to completely reconfigure the keyboard layout of my bluetooth keyboard and to get an automatic dialog on keyboard connection to adjust the input method and the app is imho pretty useful once you get it how to deal with the configuration interface. ;-)
Maybe it works for you as well and detects the input from your keyboard.
You can just give it a try as its free anyway.


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Dual SIM standby -- data and calls on different SIMs
I wanna ask about Dual SIM standby 4G phones, particularly Lenovo P70 if that makes a difference.
If I have two SIMs: (A) with a call and SMS tariff, (B) with LTE data.
If I browse the internet on (B) and someone calls me on (A), will I be notified of the call? And if so, when I answer the call, will I disconnect from the internet?

(I'm new on this site; I haven't found a dupe, but if it exists, I apologize.)

I didn't check the second case but you'll be notified that an SMS has been received and your ordinary incoming calling view would show up for an incoming call.

As far as phone calls are concerned, when you use SIM1 for a phone call, SIM  2 will be unavailable to receive calls or messages. Anybody that tries to call, the call will not go through.
As far as Data connection is concerned, when you use SIM1 for Data, and you get a call on SIM2, data connection is automatically put on hold, and will continue when the call on SIM1 is finished.

So the phone is still "listening" on the other SIM when one SIM is used for data?

Doesn't that rather depend on the dual-sim implementation used? AFAIR there are multiple implementations: one works by switching between the cards (as you describe), and another one gives true multi-sim. Not sure, as I never dug into it.

@Izzy I forgot to mention it in the post, it's only in the title: It's "dual SIM standby"

@yo' Ah, so that's what it means. OK, tnx :)

@Izzy Correct.  There are two kinds, Dual SIM Dual Standby, and Dual SIM Dual Active.  In the active mode, when a call is on one SIM, user will get a notification tone, that there is a call on the other SIM.

Has anybody tested downloading large file and receiving call on other Sim at the same time?


text:
How to connect a PC and android?
I wanted to share files between my computer and android device but always connecting them with a cable is a trouble. Is there a way to use my phone's WLAN network and my PC's WLAN to do this(without any internet connection), kind of like how Filetransfer software works on two android devices?
The file transfer software that I mention of only ranges for a short distance for android devices, I just want to use the two WLAN networks of my PC and android devices to share files between PC and my device and use no internet resources at all since the network here is not so good.

Possible duplicate of Can I connect my Android device to a laptop via WiFi to use file sharing?

There are many File Transfer Software available for Android which can transfer file wirelessly between PC and android phone, some of the most popular applications are listed below. The steps to establish a connection are very simple and given in these application only, but for Xender I have enlisted all the steps for better understanding.

Zapya
Download Link: https://play.google.com/store/apps/details?id=com.dewmobile.kuaiya.play&hl=en

SHAREit
Download Link: https://play.google.com/store/apps/details?id=com.lenovo.anyshare.gps&hl=en

Xender
This is my personal favorite and steps to connect the smartphone to PC are enlisted below.

Download: https://play.google.com/store/apps/details?id=cn.xender in your smartphone.
Open Xender and Click on Floating Action Button.
Select PC/Mac in Transfer to/from screen.
Click on Create Hotspot.
Now the application will create a hotspot in your smartphone and name of the hotspot will be presented in next screen.
Follow the onscreen steps on your phone to connect it to the PC which will be:

Connect PC to Wi-Fi network "Name of hotspot"
Open web Browser in your PC
Enter the web address which is displayed on your phone.

You have connected the phone to the PC and now you can start transferring photos, music, files etc.

Zapya WebShare
This is specifically for File Transfer between PC and smartphone only. It also allows to control Camera and display android notifications and messages in PC's Web Browser.
  Download Link: https://play.google.com/store/apps/details?id=com.dewmobile.kuaiya.web&hl=en

authors: Николай Залялов


text:
How to prevent WhatsApp (Web) from losing received media?
EDIT: The problem described happened to be related with the use of WhatsApp Web instead of WhatsApp app on the phone.
In my WhatsApp chats a couple of months old, I see placeholders for photos, videos, or voice messages. However, the photo itself is not shown, and when I click on it, the error message appears "Photo unavailable. Can't view this photo because it's no longer on your phone."
I myself have never deleted any of these photos from my phone. The message has not been deleted by the other party. I guess it's WhatsApp itself that deletes the media files after a couple of months. How do I stop this? I want all my sent or received WhatsApp media to be kept on my phone for unlimited time.

The described behavior is particular to the use of WhatsApp Web (or, maybe, also the WhatsApp app on the computer, I did not try).
I typically use WhatsApp from the web browser on the computer (WhatsApp Web), not from the phone. When I click on a media in WhatsApp Web, the media is shown, and I assumed that it would be synchronized with the phone (downloaded to the phone, saved there, and then shown on the computer). No. It is not downloaded to the phone, only to the computer. What is more, it is not saved on the computer but is only shown directly in the app.
Consequently, as time passes and the original media is no more available for download, there is no copy saved on the computer, and there was never any copy saved on the phone.
In order to have the media downloaded to the phone, you need to open the WhatsApp physically on the phone and tap the media. Presumably, after that the media would be saved to the phone and will not disappear anymore, as the other answer indicates.

WhatsApp doesn't itself delete photos. I have once faced such a problem myself, and it's nothing serious.
Here are two solutions:
1.Go to the Phone Settings > App Settings > WhatsApp and clear the cache. If possible, force stop the app too. Now, restart the aplication and it should work.
2.If the above method doesn't work, restart your phone once.
3.If your WhatsApp data (media files) is set to be stored in any external storage device (SD Card), then go to the relevant phone settings, turn off the option for external storage, and then turn it on again. The problem should be solved by now. If it still doesn't work in this case, then unmount and remount your SD Card.
Hope this helps!


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How to get the latest security updates for CyanogenMod?
I have installed CyanogenMod in February 2016, and the device information showed Android version "5.1.1", and the security patch level was "November 2015".
This hasn't changed until today (2016-02-20): The device says that there are no updates.
Looking at http://www.cyanogenmod.org/blog the last entry with "Android Security Bulletin" in the title was back in October 2015.
Looking at https://source.android.com/security/bulletin/index.html there are security bulletins for each month.
So my question is: How can I get these Android security updates for CyanogenMod?
Any information about that delay (if it's really one) is appreciated as well.
It's OK if have to compile it myself.
In case it's device specific: I am using a Samsung Galaxy S4 mini.
Update
I have probably used the "Download latest release" link on the page pointed out by xangua in his answer, and it seems that this link in fact refers to a "snapshot". I am looking for security patches for the "latest release" (v12).

Sounds like you haven't updated in a long time as at today (2016-02-20) latest nighty for that device is cm13.0 2016-02-19.
If you refer however to a snapshot, as you can see the latest available one is from November.
https://download.cyanogenmod.org/?device=serranoltexx

I see. Do I have to switch to the current version (v13) to get security patches? In other words: are there security backports from v13 to v12 at all? I just want to have a working and secure smartphone - is v13 already stable?

Switch or not is up to you, also unless you specific what exactly you consider insecure the statesmen you want a"secure smartphone"is very unclear.

Regardless of switching from a snapshot to a nighty build, you'll have to make a clean install. Also it is the snapshot that is considered "stable" as the nighty build are.....built in a daily basis.

You can't install latest security patches on older android/cyanogen/lineage/etc versions.
You will have to upgrade to latest version for your device to get that.


text:
Stop Chrome from opening Google Maps app
My Google Maps app has got broken. I think I can use the web version of Google Maps. However, Chrome is redirecting me out from the browser to the app.
How to stop Google Chrome from redirecting me to the Google Maps app?

In case any one else runs into this problem, you can stop this behavior by going to Settings -> Apps -> Google Maps and under More settings and permissions -> Open by default and disabling Open supported links to stop it from launching the app.  This works on both Android and Chromebooks to stop the Android app from launching any time a Google Map link comes up.

A few options - open the Maps app info and disable it is the easiest. I also just noticed that with the Xposed module XPrivacyLua if I block Chrome from being able to get applications no links are ever opened in another app.

Thanks, but I don't want to disable Maps, I hope it will be fixed soon, I'm going to check if the Maps app is fixed from time to time.

@YevgeniyAfanasyev slightly confused - if your Maps app is 'broken' (you should clarify a bit more btw), why would disabling it affect you? Also try going to the Maps app info and clearing defaults, then Chrome should prompt you next time and you can just hit deny.


text:
How to disable the in-app update notification on Google Photos?
When opening Google Photos and if there is a newer version, it says that I need to upgrade. You can of course click no, but it is very troublesome to do it always.
Is there any way to disable this popup without upgrading the app?
I got a rooted device.

Related: Any way to disable "update now" popup upon opening Google Photos App?

Go to the Android Settings
Find the Google Photos app
Disable background data

When you get the notification next time, long press it and you will get the Settings or the details option based on the version of Android running on your device. Once you select the option, you will be taken to the notification settings page of the app and from there you can choose to turn off the notification for that particular popup category or for the entire app.

Apparently this is a pop-up notification inside the app, not an Android system notification. AFAIK, it can't be disabled from any settings. (ref: Any way to disable "update now" popup upon opening Google Photos App?)

Alright, I have a solution, more of a workaround and not the best one, but it works for me, I used MacroDroid to dismiss that window automatically. I'm using Photos v5.52.
Application Launched (Photos) > Wait 750 ms, Repeat 7 times{Click[com.google.android.apps.photos:id/negative_button], Wait 100 ms}
It's the UI interaction action and identify in app function.
Didn't find any other solution.. tried LuckyPatcher to change some components, detaching from store, XprivacyLua, but no luck.
Macro here: http://bit.ly/3HAHwBc


text:
How to handle the Play Store country restriction for those who live in multiple countries?
I had already a lot of trouble with the Play Store country change in Canada. Now I'm living for a while in Singapore and I have the same trouble again.
In Canada/USA, I was not able to download the online banking app of my bank RBC and the service app of my phone carrier Virgin because I couldn't change my country in the Play Store. Now I have the same trouble in Singapore. Bank accounts here are not easy to get (a lot of paperwork) and will cost money. That totally blocks me from downloading free service apps.
I only have one bank account in Germany for my credit card and all payments and I want to keep it like that. I don't want to pay for other bank accounts, credit cards, or want to manage different bank accounts in many countries and currencies. I don't even want to talk about the hustle with the tax office. That was already enough with the one Canadian bank account.
Is there another way to change the Play Store country than to open a bank account with a credit card in every country you're staying in?

Note: I removed the additional question about Apple AppStore because this site focuses on Android expertise. For questions about Apple products, feel free to ask them on our sister site [apple.se].

How about just creating a new Google account for this purpose and adding it to the phone. You will obviously not need a payments profile to download the free apps. But I believe you can still create a payments profile and use your existing card (German, Canadian) in the new account. Or better just buy Google Play gift cards (the offline scratchable ones).
It is very easy to switch the account within Play Store. So, that won't hurt much.
That's the only solution I can think of. I have already had a lot of pain to revert my account country from Canada to India. Because a lot of my apps were showing as unavailable.

Thanks, I will try that. I though about that already but I was scared that I might break some google policies with it and risk to loose my accounts.


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What is "com.samsung.android.dqagent_SA_SDK" user certificate? Is it safe?
My user certificates has the following: com.samsung.android.dqagent_SA_SDK.
It seems so strange, it looks like someone put it on there. Is that normal?

From the name com.samsung.android.dqagent_SA_SDK, looks like the certificate is installed and used by DQA (also known as Device Quality Agent), a Samsung system app.
From some reports (in German and Russian), the certificate will automatically be reinstalled if it's removed, presumably by the app itself, since it also contains the certificate (from the report of reverse.it)
While I cannot certainly determine if it's safe or not, at least it's related to Samsung's own system app, so the possibility of a rogue certificate is lower (though not 0%). However, looks like you can disable the app without any side effects.


text:
Compile apps from GitHub source on device via Termux or apps?
Are there any ways to compile APKs on the device from GitHub source, like "APK builder" by heagoo? Termux method would be nice too if anyone knows.
I have tried the sdrausty.github.io method, but I believe that's more for his pre-configured APKs. I want something more universal.
Specifically, I'm looking to build this app: https://github.com/ukanth/afwall

Yes, it's possible in a universal way. See https://timeout.userpage.fu-berlin.de/apkbuilder. It's a toolchain as a Bash-script.

any app's ... that can compile apks on device from github source?

The command ~/buildAPKs/build.github.bash can build nearly an unlimited number of APKs which are available at GitHub today and is available at https://github.com/BuildAPKs/buildAPKs.
This BASH script uses aapt, ecj, dx and apksigner in Termux and Termux PRoot to make APKs on device and runs in Amazon, Android, Arch Linux, Debian, Chromebook, Ubuntu and Windows.
The https://github.com/BuildAPKs/db.BuildAPKs repository has build results for a few of the accounts at GitHub.  For example, the B10NAMES file has GitHub login names that built at least 10 APKs on device in Termux.

Specifically, I'm looking to build this app: https://github.com/ukanth/afwall

$ ~/buildAPKs/build.github.bash https://github.com/ukanth/
build.github.bash: Beginning BuildAPKs with build.github.bash https://github.com/ukanth/:
.
.
.
Results for ukanth:
com.ukanth.simplebatterytemp.apk
com.andraskindler.quickscroll.apk
com.stericson.RootShell.apk

The app afwall does not build on the fly with BuildAPKs at present.  Three of ukanth's apps do build on device in Termux on Android out of box.  With modifications to this script, afwall should also build on device today.


text:
How to press & long press the "back" key with a terminal command?
We manage Zebra Mobile computing units running on Android 6.0 Marshmallow through an MDM. For some reason, the MDM interface doesn't show the Android buttons at the bottom of the screen (back, home, menu, etc).
I was able to find the script for the home screen on this site.
Is there a way to send the script for other buttons as well?

Have you tried KeyEvents? ADB Shell Input Events

adb shell input keyevent 4 this should trigger the back key


text:
Convert OTA stock firmware zip into image file for recovery using SD card
I have a bricked TV Box MeCool HM8 and I need to restore it to factory settings. Unfortunately, I have the stock firmware in zip format. I need to convert it into image format to be able to use an SD card for recovery.
Any help, or advice, would be appreciated.

I thought you were able to load ZIP files from recovery menu. What makes you think you need an Image file?

I cannot get to the recovery menu ,the box is not responding ,just the dreaded red light is showing ..


text:
How to Block Pre-Installed Auto App Installer Malware?

I dont know which pre-installed app is auto installing new apps.
But I think its com.android.system.service (also on few other phones: http://en.miui.com/thread-459132-1-1.html)
Firewall is not supported for this old OS phone (I think its gingerbread)
Also No root available for my phone. I also tried all auto rooting apps for android and PC.
Because its old Android OS, there is no option to disable any pre-installed app.
I think antivirus is deleting only few harmful apps which are downloaded by pre-installed malware app.

The malware app is downloading apps to a hidden folder (.sysAndroid/Download) in sd card, I have no threat to my internal memory because its full.
How to make a folder on sd card unwriteable without root or with any trick?
like making a fake folder with same name to stop virus app from saving new apps in folder again(.sysAndroid or Download)
Or any other method?

What phone model is that?

First, you could make that folder "un-writeable" easily without rooting. As it's located on the SD card, and you're on a pre-Kitkat device, any app should have full access there:

Get yourself a file manager
navigate to /sdcard/.sysAndroid
delete the Download folder
create a new text file called Download, and make it read-only

Now, that malware app can no longer create the directory, as a file with the same name is in that place.
For other measures, we'd need more details (and I could update my answer then):

go to Settings › About Phone and check what Android version is running on the device
find out which app is installing the unwanted apps. I didn't test it with pre-Icecream devices, but my tool Adebar should be capable of that¹: Among other things (which require at least Kitkat), it creates a list of apps installed on the device, grouped by their installer (see here for an example: as you will notice, the package name of the installer is noted along). If your Android version indeed is older than 4, you most likely will not be able to "kill" that app, but other measures might be known.

¹ Adebar will require adb installed on your computer, and Bash being available – so a Linux machine is best suited for that. But it's reported to work well on a Mac, and even on a Windows machine running Cygwin.

The file trick worked. I can't check android version in "about phone settings" because phone manufacturer edited that text to a later version which is fake. Phone interface, gallery looks like its gingerbread.

OK, that makes it harder. Icons in the notification bar are green I guess? Well, as the file trick worked for you, the original issue seems to be solved. Though it would still be interesting to hunt down the culprit. Who knows what else it has in cue. If you're interested in that, I'd suggest you ask a specific question on it (a la "how to identify the app which installs other apps on my device"). We could check Adebar's "ADB tricks" on that manually then (after all, it's just executing some ADB commands and evaluating the results).

malware app is not downloading new apps but still auto installing 1 app again and again without any visible downloaded apk (I check all apks from default file manager > Apks). What should I do now? Thanks for your help!

Have you tried Adebar yet, to find out which app is performing those installs? If so, is it a system app or one you've installed yourself?

I am using phone setting to install apps only in internal memory, so malware app can't install new apps on sd card but in internal memory. Because I thought problem solved I cleaned internal memory but after I know it  can still install a new app in internal memory I again filled internal memory. Now again phone is working better. I am 100% sure that it is a system app because I already checked by uninstalling every single app installed by me. Now should I use Adebar ? (My phone is gingerbread with a preinstalled malweare app)

Up to you. You can also try to analyze it manually, evaluating adb shell "dumpsys packages" output, if you prefer.


text:
What do "Installed", "Running", and "All" apps mean in Android Settings?
I have an Android device running on Android 4.4.4. In the Settings, I have no idea what "Installed", "Running", and "All" apps are.
What do those mean?

The menu in Settings › Apps usually has multiple tabs (or items in a drop-down), signifying a (sub) group of the apps available on your device:

Installed: user-installed apps. Most of them are those you installed yourself, but some might be "vendor-provided" apps that got installed on initialization (first use or after a factory-reset). These are the apps you also can uninstall.
All: All apps, whether pre-installed or user-installed. This is the only group where (pre-installed) system apps are shown as well; these you normally cannot uninstall, but only disable (and sometimes not even that).
Running: These are the apps currently running – either because you started them explicitly, or because they got started by some intent (in most cases, this is BOOT_COMPLETED, i.e. apps starting automatically after boot – but it also could be something else they're reacting on, such as network state changed, or some other app calling them as it often is the case with Maps)
Disabled: On some devices, you might see this as explicit section listing the (system) apps you've disabled. On other devices, this section might be missing; disabled apps then carry the string "disabled" next to their names in the "All" section.


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How to back up notes from Samsung Notes app?
I use Samsung Notes (in Samsung Galaxy Tab S3) daily for taking notes and audio from college lectures. But how can I get all of my files and store them on my external HDD?
I mean, there's no file inside the tablet's storage, nor inside my SD card. Moreover, I wouldn't like to synchronize any of my notes and audio with Samsung Cloud or something.
How can I retrieve my Samsung Notes files and audio?

I've never been a user of Samsung so I'm not sure how the stock Notes app works and in what format it saves files. This question indicates that notes can be backed up to PC from a Samsung phone using Kies as .ssm files and subsequently be opened using some media player (like VLC / Real Player) or S Note app.
This question addresses different methods to backup .memo or .smm or .spd files created by Samsung Memo app (if it's the same what you mentioned as Notes app). Memos can be shared/exported one by one in readable text files or otherwise transfer the memo files to PC.
Now, app data is always saved in one of these 2 locations: /data/data/package-name or /sdcard/Android/data/package-name. Package name of Samsung Memo app is com.samsung.android.app.memo as mentioned here but you can check yours from App info. Accessing the former needs root access. Also an app with permission.WRITE_EXTERNAL_STORAGE can save files anywhere on /sdcard. Samsung Memo app version 1.0.4517634 app saves it's files to /sdcard/BeamMemo. For other versions, it can be different; /sdcard/.ActionMemo or /sdcard/SNote Data. You can search for these files using some File Explorer app or find command through commandline.
Once the backup is done, you can either:

Restore these files back to phone later on. In this case you should backup the whole folders and not only the memo files. But still it's not guaranteed that the app will recover whole data if it is reinstalled unless a backup file(s) is created by the app for restore purpose. If you are restoring to /data/data/, app UID and SELinux context also need to be restored.
Open these files on PC. .memo files are basically zip files which can be extracted to get media files and text contents as answered here.

Or you can use a free app like ColorNote (for text-only notes) or other one which is easy to backup and restore.


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Setting up Python so that it can be run on any Android terminal apps
I'm trying to get Python 3 to run natively on Android. By "native", I mean native Linux, just an Android variation of it. I'd like to be able to simply open a terminal and type python /path/to/script.py, so Kivy and Qslide will not work (to my knowledge, feel free to prove me wrong). Normally, Termux would do this, but I don't like the terminal app just the Linux packages it supplies, prefer to use another called Terminal Emulator by Jackpal.
I've tried booting into TWRP (I don't have root otherwise) and copying the necessary Python binaries and lib folder and the Termux data directory to /system/bin and /system/lib, but Python fails, saying it can't find libandroid-support.so. I realize Termux's Python is probably modified in some way to account for the directory structure required by an Android app and therefore couldn't find the .so even after I copied it to /system/lib.
So my question(s) are: How might I make the solution I tried work? Are there any other ways to get Python installed as a native Linux app*?

*Like I said, I want it to be just like on a desktop Linux where I can open ANY terminal app and use python just like any other command.

Why don't you simply run a Linux distro on Android device? It's fun to have power. But that needs root and in some cases a custom built kernel for chroot, namespaces etc. No apps need to be installed other than a simple terminal emulator. Termux packages won't work that way because paths of linked libraries are hard coded. Also, most of the Termux packages or other Android specific solutions are limited one way or the other.

@IrfanLatif how about drivers if we need access to peripheral devices?

I believe the solution for you is Python-for-Android (Py4A). Not only does it allow you to run scripts on your Android device, but you can go one step further because the project includes simple draft instructions on creating a standalone, downloadable Android APK package.
First, I would start by going to the readme section of Py4A. There is a recipes (script) that will fit your needs. The python3 recipe allows Python3 to run as a "standalone" on Android.
This excerpt from Linux Journal explains script installation on your Android device:

Running on a Smartphone
To run a Python script on your physical Android device, install SL4A together with Python for Android on your handset, then transfer your script.
To install SL4A on your physical Android device, enable the Unknown Sources option in your device's Application settings. This setting is required to enable the installation of non-Market apps on your phone. With this done, you can follow the same steps you used when installing SL4A and Python on your emulator. To speed things up a little, install Barcode Scanner from the Android Market and use it to “read” the QR Codes from your desktop screen.
Transferring Your Script to Your Handset
There are a number of ways to get your script onto a real phone. I've found the success of using something like Bluetooth connectivity or USB cabling arrangements can very much depend on the hardware on which you're running. What works on one handset, doesn't on another, and so on. Your mileage may vary depending on your actual device. When I need to transfer a file, I've come to rely on a solution that works no matter which handset I use (as long as the handset can talk to a local Wi-Fi network). What I do is switch on the OpenSSH server on my development PC running Linux, then use the AndFTP file transfer app on the handset to scp files from the desktop to the phone. AndFTP is available from the Android Market as a free download and installs in minutes. Once I connect to my desktop with AndFTP, I can navigate to a directory of my choice, mark the files that I want, then download them to my SD card on the handset.
AndFTP works well, and I've come to depend on it for all my Android file transfers (see Resources). Just be sure to transfer your scripts to /sdcard/sl4a/scripts on the phone to ensure that your script names appear within the SL4A list of scripts.
With your script file transferred to your physical device, start SL4A as before, tap your app's name and tap the run wheel. As expected, your app runs just as it did on the emulator, only faster! I haven't included a screenshot of the app running on a real phone for two reasons. First, it looks exactly the same as it did in the emulator, and second, it's running on your device, so you can take a look at it there!
Creating an APK
There's one further kink to SL4A that might interest you. The project includes draft instructions on creating a standalone, downloadable Android APK package (see Resources). Once created, the APK file bundles your custom Python script with information that allows other Android users to install Python for Android automatically onto their handsets and then run your app from the smartphone's main menu of apps. Describing the process of creating the APK likely would take another article, so I leave it to the brave among you to try out the instructions on the SL4A Wiki"

Python-for-Android website.

Not all devices allow runnng Linux within android and I've hard bricked a phone by deleting the Linux directory and having symlinks to Androids own system files followed so I really don't like that option.

Would it be possible to compile Python 3 from https://github.com/python/cpython/tree/master/Python on Android (hopefully with little to no modification to fix path variables) and (lacking a package manager for Linux apps) move everything into place from TWRP?

@Myersj281 vendors never want you run anything on the device other than their officially provided ROM. It's in their great benefit and also in user's benefit if he/she doesn't like playing with technicalities. Unlocking bootloaders, rooting, custom kernels, custom ROMs, everything has some degree of risk with it. But it gives you freedom. I've been using a lot of native code on my Android phone for last 2 years, including multiple Linux distros (Ubuntu, Debian, Void, ArchLinux) without any loss. My use is compiling programs natively rather than using cross compilers on PC. But it's a choice :)

True symlink can make things weird. Is this the symlink you mentioned: ln -sf "${TOOL_PREFIX}/sysroot/usr/include/"{linux,sys}"/soundcard.h" or ln -sf $(NDK_SYSROOT)/usr/include/linux/soundcard.h \ if so look at the path variable it includes sysroot. The sysroot is actually a merer copy of the file system of your target platform. Which is a directory which is considered to be the root directory for the purpose of locating headers and libraries. I suppose you can replace the sysroot option with another option. sysroot makes things less compilcated or change the crosscompiler.

@Myersj281 forgot to tag you first comment. Anyway, is it possible? most likely yes but difficult make it work. In my experience crosscompiling can be difficult but its easier than after its compiled figuring out, researching, and fixing thing to get it to work and be usable. It can get very frustratingat least for me. I quickly scanned through source code for sl4a and python3. I did not see any rm (delete) of a linux directory. Could you give a link the source file where the the linux directory is deleted please??

@ Bo Lawson: My bad. That's not a part of my problem here. @irfan latif suggested I try that option and I have done that before on another phone for different purposes and had bricked that phone in the process of removing the Linux directory (chroot container) so I don't like running Linux within Android. though to answer your question anyway I believe the symlinks pointed to files in the /sys and /dev directories (in Android) but I could be wrong. As for the sysroot idea you had, I think you were refering to the chroot thing but that is a good idea that might work here!

Wow. I've been checking out some files mentioned in https://devguide.python.org/porting/ and I'm realizing there's a lot of work beyond simply editing path variables and that I am definately not skilled enough of a programmer to port something as complex as Python to the version of Linux underlying Android! :(

Nope, I was referring to sysroot. Her is the documentation it is a little bit over halfway down this Controlling the Compilation Driver, gcc tutorial: http://gcc.gnu.org/onlinedocs/gccint/Driver.html#Driver Porting and Crosscompiling stuff is a lot of work. I is interesting and very frustrating. However, you learn a lot through the research involved in trying to make things work. I. Have just ported and cross-compiled a few ROM's to different devicesThis is a simple guide explaining the cross-compiling process: https://forum.xda-developers.com/showthread.php?t=2723240


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What are "minuhome.Black.[...]" apps?
I've downloaded an app locker on my Samsung Galaxy Note 8, and as I was trying to import apps to the locker, on category "M" of the app list comes out a lot of Android icons with the file name of minuhome.Black.[...].

What are these apps? Am I being hacked?

Based on googling "minuhome", looks like it's Samsung Galaxy's launcher/theme app.

Minu is one of the themers who makes Samsung themes. Those are all the overlays for every package that the theme themes. If you want to removee them you'll have to remove the theme, but they're all small and they don't contain any code at all, just resources (XMLs, PNGs, voctors, etc.)


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Can not re-sign Android system app without app crashing (using LineageOS)
The original post on Reddit with some more background about the issue.

I have re-signed all system apps of LineageOS with my own key and have replaced them all before the first boot. LineageOS boots normally but then all re-signed system apps crash with an error like:
SystemUI has stopped, Settings has stopped.

The screen stays dark. It seems that the re-signed system apps are unusable. Maybe I made some mistake or LineageOS has some anti-tampering check implemented?

What I have done: I opened all system apps with the WinRAR zip manager and removed the CERT.RSA and CERT.SF files in each META-INF folder and deleted all the names and SHA-256 digest entries in all MF manifest-files. Also, all other APK for example, in the framework folder, like the framework-res.apk file, I edited them like this. Then I created a keystore with Key, using the Java keytool, I think this is self-signed. Then I signed all APKs with the Uber Apk signet tool and successfully performed zip-aligning. Then I flashed Lineage OS with TWRP on the phone. Before the first boot, I deleted the system APKs with the TWRP file manager and replaced them with my self-signed ones. Uber-Sign-Tool: https://github.com/patrickfav/uber-apk-signer

I have now adapted with the TWRP terminal chmod with the following commands: Before I adapted chmod, I checked everything with ls -l.
Then I adjusted everything as it is right in the system so for me: chmod 644 for system-apk's and the apk-folders and chmod 755 for the /system/app and /system/priv-app folders. Now I'm stuck again in bootloop when I edit chmod.
The chown-Settings were already on root. Also I tried chown 0.0 -R and chcon u: object_r: system_file: s0 (see also installing apk in /system/app with android 5.1 or higher (simple adb push doesn't work anynore) push does) I stuck again in bootloop when I edit chmod.
There are no Odex files available.
Why can I edit the AndroidManifest.xml from all Systemapps without problems if I keep the original signature except at the framework-res.apk? Does anyone know why it doesn't work with the framework-res.apk? The only way I find which works is to turn off signature verification in the whole system, but this is bad for the security.

Did you chmod and chown system/app recursively to fix permissions and ownership. ---
If so.. Is the system deodexed or odexed, the odex files could be mismatched with the apks... Also.. I usually don't sign system apps at all, i find that they aren't usually signed anyway... i think signatures mainly matter for DATA apps, and apps that use shared userID's

Hmm, not sure if it still is the case in recent Android versions, but at least in Nougat what I did is keeping the original signature while modifying framework-res. apktool has the -c option for that, though yes you will lose AndroidManifest.xml changes, so it might not work for you. What I want to say is that the OS likely does check for that signature.

I edited the Post


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Make android phone as USB Webcam
I have an Android tablet based on Android Lollipop (5.1.1) and I want to use this device as a webcam via USB.
I know some apps could work (e.g. DroidCam or WO WebCam) but they require extra clients installed on a Windows / Linux computer.
Is there any way that I can add an extra option to the USB connection settings that will allow the tablet to be used as a webcam instead of a media device?
Please note I am not asking for apps that can read videos from OTG USB webcams. It's the reverse, making Android output a video feed to a separate computer via USB.

Does your tablet support HDMI/MHL over USB?  Otherwise this could require kernel hacks. You're trying to do something with a device which was never meant to do it, so...

No Device does not support HDMI/MHL over USB.

@TamoghnaChowdhury can suggest me where to change in kernel?

I can't, and neither can anyone else on this site. This is because kernel hacks relate to development, and development-related questions are considered off-topic on this site. You may have more luck over at the XDA forums for your device.

Driodcam works fine for mine Lenovo tablet- skype and all video programs now recognize it as camera, therwise, i havent found anything that works, tried vysor, but that didnt work....


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Intermittent internet connectivity problems on Samsung Galaxy S4
So last night Chrome on my Galaxy S4 suddenly started refusing to load websites while connected to the exact same WiFi network that works flawlessly for two different laptops and a PC within my home network. Even using two different mobile providers' data networks, or the WiFi at three different friends' houses doesn't seem to work, so I doubt this issue has anything to do with my internet connection/s.
The strangest thing about this whole situation is that Chrome will search Google fine, and the Play store app will also search its catalog, download updates and even install new apps without a hitch, but pretty much every time I try to connect to a non-Google-owned server, the connection status bar fills about 10% of the way and hangs for 30 seconds before timing out.
Has anyone experienced anything like this before?
EDIT: This now happens at least once per day; often 3 or 4 times per day. Restarting the phone seems to be the only way to get connectivity back, before it drops out again a few hours later. Google apps (Play Store, YouTube, Maps, etc.) all work fine without a restart but other apps and websites refuse to respond. Please help; this is driving me crazy!!


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Why do I have Aptoide app installed, and why do update to apps that I didn't install shown on there?
I found this “Aptoide” app on my Samsung Galaxy A5 the other day but I certainly don’t recall downloading it. I opened it up and somehow got to the updates section. It showed me available updates for a bunch of apps, some of which I have but others I don’t. I’m wondering if one of my kids might be up to something on my phone and need some guidance. It shows a list of apps that have pending “updates” and then below it, it shows a list of “installed apps”. There is a weird messenger app called “Messagerie double” that you can see in one of the images. I don’t see that app anywhere on my phone and I guarantee I never downloaded it.
I’ve attached photos for example.

Apps I’ve never downloaded include:

Messagerie double
SEMFactoryApp
SVC Agent
Network Diagnostic
slocation (Another one not pictured but the same green Android logo)
bootagent (Another one not pictured but the same green Android logo)

Does its presence under Aptoides “Updates” section indicate it does reside somewhere, hidden on my phone? And if so, how do I access it? Am I right to suspect these are somehow being used on my phone without my knowledge?

After some research this is what I came up with.
Did you download an APK for some app from the Aptoide website recently? If so, you didn't download that app. You downloaded the Aptoide market, and that market downloaded your app. It is likely that one of the kids tried to free download a paid app, as I see there are a lot of them in Aptoide. :) As always those free market apps are not trustworthy at best (they may look clean enough but they might still be sending sensitive data to their servers), and malicious and virus-infected at worst.
Here is a list of what I came up with each of the apps you mentioned:

"Messagerie Double" means "Double Messaging". I didn't find anything specially useful about this app, but based on what I've seen it looks like the Samsung Dual Messaging function, hence a system app.
"SEMFactoryApp" should be a system app, as it was mentioned in this Reddit Thread. Also, this JoeSandbox analysis dodn't detect any suspicious code in this app, so it looks like it's safe to assume that it is a system app.
"SVC Agent" looks like it matches com.samsung.android.svcagent, which is in this debloat list on XDA, and this thread on Android Authority also mentions that, so it looks like a system app too.
"NetworkDiagnostic" is mentioned on this APKMirror page as having package name com.samsung.android.networkdiagnostic and it is also in the debloat list above, so likely a system app.
"slocation" looks like a system app too, considering it didn't go away after a system reset as mentioned here.
Finally "bootagent" also looks like a system app, refer to post #147 here.

So why does Aptoide display system apps? Because it doesn't distinguish between system and non-system apps, and someone named sirkesyone-applikes (clearly without a proper knowledge of system apps) uploaded those system apps to Aptoide. If you or one of the kids mistakenly hit "Update" and confirm the update on one of those apps it could update to a wrong or incompatible version and brick your phone or erase your data or etc. So I would recommend uninstalling Aptoide as quickly as possible. :)
Good Luck!

As always those free market apps are not trustworthy at best, and malicious and virus-infected at worst. Not all alternative markets are virus infected or untrustworthy see https://android.stackexchange.com/questions/216/what-are-the-alternative-android-app-markets. I think should backup that statement with a link.

Maybe "not trustworthy" is a bit strong... What I meant to say is, just use with care. Even though an app is clean looking and doesn't do anything that looks bad, it don't mean that it doesn't do anything bad, or never will. :) It could still send encrypted sensitive data to servers, or the app could change if some other company purchases it.

Agree. We should all be careful even when using Google Playstore.

Yes, I feel the number of malicious apps being discovered in Play Store is higher than usual lately, and Play Store isn't open source either. :/


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Turn off TalkBack/double tap on Samsung Galaxy Tab A 10.1
On the Samsung Galaxy Tab A 10.1, after downloading the latest OS, some settings got changed and the TalkBack comes on. However, I cannot find a TalkBack accessibility item to turn off.
What's the workaround to shut this off/remove it?

The TalkBack feature is now called "Voice Assistant" and accessible through Settings > Accessibility > Voice Assistant. From there, you can turn it off.


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How can I make my Google Calendar make sounds when an event is about to begin?
I have OnePlus 3 running Android 8.0 (OxygenOS 5). It currently just shows one notification for every notification I add in the app for an event.
How can I make my Google Calendar make sounds when an event is about to begin?
This is the notification settings for Calendar notifications:

You can add additional default notifications in the Google Calendar app.
Inside the app, open the Settings menu. Then tap on the calendar you want to add more notifications to. You'll see a screen like this:
(this is for my calendar named "Events")

If you tap on "Add another notification" there you can add as many notifications as you'd like, up to one minute before the event starts.
This will result in changing the defaults for every new event you add - for existing events, you'll have to edit them individually to add more notifications.


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Insufficient storage space & Insert SD card
I'm using a Meizu M6 and a newly bought Sandisk Ultra Micro SD XC 64 GB.
Internal storage is about 1.67 GB free out of 16 GB. My SD card's system was FAT32; reformatted it to exFat, now the phone won't read it (still working fine with desktop). Android version is apparently based on Nougat, OS is Flyme 7.1 Global. Phone file explorer is built-in/default; desktop is Windows Explorer.
So my phone and desktop can detect my SD, but:

Every time I tried to create an empty, new folder on my SD, it gave me the "insufficient storage space" message, despite being empty as a clean slate.
Every time I tried to use the camera, it gave me the "insert SD card" message, despite being able to detect it earlier.

Yet I can create new folders and move items to my SD if I connect it to my PC with some card reader.
For the record, I have already checked the wiki tags and similar topics, as well as format, remount, cache clear, and/or reboot, but none of them worked.
The SD card worked fine in another phone (Realmi2Pro, with a custom OS). For now, we suspect it's the problem with Flyme 7 OS.
What might cause this? Any pointers?

You need to grant write access (uri tree permission) to external sd card through Android Storage Access Framework. What filesystem do you have on sd card? What Android version you are using? What file explorer did you use to create folder?

you could try using the Windows partition manager to format the micro sd card and create a brand new partition. You could try using the tool h2testw to check if the card is damaged or authentic.


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Why did my Galaxy Tab 7.7 suddenly stopped connecting to my Wifi router?
I have Galaxy Tab 7.7 tablet running Android 3.2. Recently, I'm having connection problems to my home Wifi router. The device keeps scanning for Wifi access points for long periods. My home Wifi router is shown with a "Not in range" message next to it in the Wifi settings screen. However, sometimes after long period of time, the device randomly connects to the Wifi router.
It is worth mentioning that during the scanning mode the device does not detect any Wifi access point even thought where I live there are many Wifi access points (over 8 access points).
What is the solution to my problem?

I had the very same case a while ago with my HTC Wildfire, after having flashed CM7 over the stock ROM. It solved when I also updated the radio firmware, and now still runs fine with CM9.1. If you made similar changes, this might be worth a try; otherwise I don't know anything apart from a Dalvik Wipe or factory reset.

@Izzy Thanks God. No need for factory hard reset :)

The solution turns out very trivial and surprising. It shows and proves practically that the behavior of complex software systems is unpredictable.
The solution:
Go to Mobile network settings and disable Use packet data. Next, enable Wifi and then go back and enable Use packet data.
Magically, all my problems disappeared after I applied described steps.

Woah! who would have thought of that... Glad it solved that easy, and (even better) did not need a factory reset!

I guess there is some conflict between the code that handles Wifi functions and the code handling 3G networking functions.

I was having the same problem, but I can connect easily at home (automatic) but my problem was at work.  I just changed some of the settings.  Turned connections optimizer (yesterday in order to connect I had to turn it off) and reset wi-fi timer for 7a-5p.  We'll see how that works once I get home.  The settings have been on set for approx. 10 min and I haven't lost the signal.  Decreased but not lost.


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Unable to update system app
I have been trying to update the system apps on my android phone, where in I get an error mentioning that the application which I'm downloading can't be installed. (Error code :- 104)
When I searched this problem on the internet, most solutions say "You have to root your cell phone and then try to update/install the respective application on your phone."
As I don't want to root my phone, is there any better solution to solve this problem instead of rooting my phone ?
And when I tried to install updated .apk file externally it shows error

On the 104 error, Google support suggests to follow the I can't download from or load the Google Play Store troubleshooting guide link (switch off the device, wait a few minutes, switch it on and try again). Could you please verify whether it works for you?

No I am not getting it, As you are saying i tried all the step's which is given by play store and still I am not able to update applications

Click on settings > backup and reset > factory reset then say yes to clean your phone.
If you try to factory reset your phone, this will do your phone automatically update your phone with initial version of your applications.
Then try to update your respective built-in application from play store, it will solve your solution.

The OP wants to update stock apps via Play Store.

If you factory-reset your device, that doesn't "automatically update your phone with initial version of your applications" but simply remove all updates, configurations, etc. – see our factory-reset tag-wiki for details. As a side-effect it will also clear the cache of Google Play Store, which might solve this issue (or not); but that's like killing a fly with atomics if you don't even know where the fly sits.

Removing all updates, configurations, etc also means the same which is nothing but it brings back to initial version.

Open App Info of Google Play, clear cache and/or data and try updating the app again, should help in resolving that error.
If it doesn't help, and you require the update urgently, try downloading an APK file of that particular app, enable "Unknown sources" in Settings > Security, and open the downloaded APK using PackageInstaller. A good source to find the APK file of the app is APKMirror.

I updated the question and added an image of showing error when I tried to install updated .apk file

@VijayGupta basically that means you already have the updated app.

No I checked application version that was an older verson, whose update is showing in play store

Actually you need to take a build of apk and sign with google with the system/laptop from which you take a base apk uploaded in google play store.
Because conflict in signature(SHA) key of system will lead to this error while updating the application.
you can get system SHA key using below terminal command
keytool -list -v -keystore ~/.android/debug.keystore -alias androiddebugkey -storepass android -keypass android


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Install Google Play on Android SDK Emulator
How can I install google play on the Android SDK Emulator? I start my emulator like this:
./emulator -avd my_custom_device_API_26 -dns-server 8.8.8.8 -writable-system

and I tried it How to install Google Play services on an Android 6.0 emulator?, but it doesn't work. Although I'm staring emulator as writable, I get:
remote couldn't create file: Read-only file system

Also, I've bit different APKs as mentioned in that answer namely: PrebuiltGmsCorePix.apk instead GmsCore.apk and I can't find GoogleLoginService.apk. I have the Open GApps 8.1 Pico version. I've also tried to install APKs but was unsuccessful.

You need to elevate to root access to mount RW. Try adb root then adb remount then push and install your package.

For that, you have to install the Google Play image from the Android Studio SDK Manager. But you can't get it for API level below 24

Other comments don't mention it, but after installing the Google Play you also need to create an emulator again (there will be +Store in the description)

Hiya! Make sure when answering that you're still giving a full solution to the question being asked. For situations like this, it's common to point to other answers as what to follow for a setup, then continue with the extra details you feel are necessary.

Remember that to display all those submenus you have to tick Show Package Details on Android SDK setting:

Also the download may be about 2GB but on hard drive may take 10GB once decompressed.