text:
Calibrating/Correctly draining an Extended Battery
I recently purchased an extended battery for my ailing Galaxy S4. It's supposedly rated at 4000 mAh over the previous 2600 mAh OEM battery.
First time I threw it in, I turned on the phone, chucked in the battery, and sat it on the charger for an hour or so.
It actually lasted a pretty long time. About 2 days and 5/6 hrs. SoT (not fantastic for 4000 mAh, but it's new so what the heck).
So, listening to the advice of others, I threw it on the charger until completely topped off while the phone was shut down. Again, I discharged it from 100%. However, this time, the battery drained much faster than usual. There weren't any particular apps draining the battery, it just drained faster.
Seeing as this was strange, I drained it to 0%, and charged it back up. Still, the same terrible battery drain. It may be I have to cycle it a couple more times.
Advice? How should I correctly calibrate an extended battery?

Good that the problem is resolved. You can post your solution and accept it to show that it was ROM related and not battery files as I suspected ( deleting my answer not being pertinent in your case). On second thoughts, your mention  within fine first time should have triggered that alternative. I was blind to it

Firstly, battery calibration is a myth, normal or extended battery. See Bought a new battery, do I need to calibrate it?
Next, with extended batteries, there is always a possibility that the correct capacity of the battery is not being read  by the ROM and displayed ( since there are two different sources for reading the battery capacity and it may be reading from the hardcoded (ROM) rather than battery capacity files. See for more details here Where are the battery capacity files located?)

What you can do

Measure the actual capacity of your battery as explained here How to determine maximum capacity of a battery in mAh? - received fake battery using the app mentioned.
Adjust the capacity of the battery manually in the app (from Battery Manager → Tap the 4 small square icon → Adjust Capacity or use Configuration Wizard) and create a shortcut on your home screen for the Battery Mgr widget and use that to measure

You can optionally avoid the first step above if you trust the battery provider capacity and adjust on the app

Thanks for your answer! As a rooted user, I deleted the batterystats.bin file, but apparently that's wiped at full battery capacity as well.

Sorry, accidentally pressed enter. My GS4 has it's battery files in /sys/devices/platform/sec-battery, but average capacity and min/low are unreadable by root explorer. I will discharge and recharge this battery a few more times and see how it goes.

Battery stats. Bin here re created when fully charged or on booting -that's a part of the reason, calibration is a myth as mentioned in my linked answer 2. Do not know about your device battery files so no comment 3. I think you may not have understood my answer, so let me clarify //

Your device ROM may be reading the battery capacity files from the location you mentioned, since the ROM knows the expected Max capacity of battery as stored there. It can't recognise a new battery with larger capacity. Hence, usage ratings are wrong.Using the app mentioned, you can force the app to read the new capacity as explained in answer. This will correctly determine usage stats. Only disadvantage of this is that it won't change the notification status of battery but you will have to depend on the app readings instead. This is my best guess. Putting it through more discharge//

Cycles is not going to help. Use the app to force read new capacity and then see if the usage makes sense

Thanks for your help. I reflashed my ROM and after another 2 discharges the battery meter as well as battery life has markedly improved.


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What is covered by "Encrypt phone"?
On Ice Cream Sandwich (CyanogenMod 9), Under Settings > Security there is an option to "Encrypt phone". I understand that this will require me to provide a PIN whenever I start up my phone. But what wasn't explained was if it covers the micro SD data as well?
I want to make it so that in case my phone gets stolen, the thief won't be able to simply get my micro SD card and pop it in to a card reader and view its contents, some of which may be sensitive.

Encrypt phone only encrypts the /data partition.
Encrypting the SD card is a separate function and isn't implemented in stock android.  Some manufacturers (I know Motorola and Samsung do) extend the encryption (optionally.  Where you find "encrypt phone", you'll also find an "encrypt SD card" option) to the SD card.  I can't determine whether cyanogenmod implements such a function or if it may be device-specific.

Can you suggest a way to encrypt micro SD as well then?

@Propeller - AFAIK, your only option would be to find a ROM for your device that offers that functionality.

source: Stack Exchange

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

sort: votes


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How to fix download notifications?
From what it looks like, Facebook is just downloading an update, but it is not downloading anything. Even after multiple reboots and uninstalling Facebook app, it still continues. How to clear this up?
Phone is Samsung Galaxy S3 running Android 4.1.2. With default TuchWiz launcher.

Try:
-Long pressing the notification.
-A small dialog that says "App Info" will appear.
-Press "App Info"
-Press "Force Stop".

I did the same and it fixed the issue. Also, cleared cache for this 'download' app. It was really frustrating to see this kind of issues..

Just go in
downloads-->select other downloads( and it will appear facebook build 141046) -->select it -->click cancel
OR
settings-->apps-->all-->download manager-->force stop
disable and clear cache then enable again

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


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GMail attachment download does not complete
I am using Jelly Bean on a Samsung Galaxy Tab 2 7.0. I have been trying to download an attachment from the GMail app. All I see is a progress bar which shows 0% progress and an icon added in the notification area. The download does not proceed beyond 0%. I restarted the tablet and the icon is back! But the download stays at 0% and does not progress.
Has anyone else faced this problem? How do I remove the icon from the notification area?

See: Download stuck in Gmail. Not quite the identical problem, but the same solution might apply.

Glad to read! As suggested, I described the required steps with an answer below.

Though not the identical issue, the solution provided with the question Download stuck in Gmail solves it as well:
Clear the cache of the Download manager. To do so, go to Settings→Apps→Manage Apps, switch to the "All" Tab, scroll to the "Download Manager". Tap that entry, and hit the button labeled "Clear Cache". Optionally, also tap "Clear Data", if cache-cleaning alone does not solve the issue.

"Clear Data" is what did it.

Not a double meaning, so no pun intended: Thanks for clearification :)

I had the same problem with 5.1 Lollipop. What fixed it: Clear Cache + Clear Data on both Download Manager & Downloads apps, then reboot phone. I also had strange problems with installing / updating apps (particularly: Dropbox) via Google Play shortly before GMail started to show symptoms. Cleaning up as stated above fixed those, too.

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


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Why doesn't my android start daydreaming?
In Settings > Display > Daydream I have
- selected one (any one, but right now it's just the standard Clock)
- when to daydream = either docked or charging
- "start now" works fine.
I've connected my Nexus 4 by USB cable to a wall charger and "Clock" confirms Charging (AC), 45%
Settings > Display > Sleep is set to 15 seconds while I try to get daydreaming to work. If/when it works, I'll probably set it to 2 minutes.
Despite the above settings, and being on AC power, the phone never daydreams. Why not?
This is a Nexus 4 with stock 4.2.2, not rooted, not superuser'ed (yet).

FWIW, I also have a Nexus 4 (4.2.2) and it daydreams OK when charging (USB to wall charger) when set to sleep after 15 seconds. Presumably it does sleep after the allotted time? Is it possible there is a running app preventing it from daydreaming?!

@w3d - In developer options, "stay awake" is checked, otherwise the screen would just turn off, right? How could daydream even work if this is off? ... Actually, I just unchecked that to try it out, and now it works! Post your comment as an answer so I can accept it! :-D

Although "Daydream" is activated when the device sleeps and essentially overrides the devices default behaviour when the device would normally sleep. If "Stay awake" is checked then the device never triggers "sleep mode". Most people never need to go into "Developer options" (it is, after all, hidden by default on Android 4.2+), so making this a requirement would be tricky for most. "Daydream" is like a conditional "stay awake".

As mentioned in comments, I also have a Nexus 4 (4.2.2) and it daydreams OK when charging (USB to wall charger) when set to sleep after 15 seconds.
"Daydreaming" is triggered when the device goes to sleep (or when sleep mode would normally be triggered). It would seem that if the "stay awake" option is checked in "Developer options" then sleep mode is never triggered and the device never daydreams. So, the solution is to uncheck the "stay awake" option.
"Daydream" is like a conditional stay-awake option. The screen does not switch off and for this reason a device can only be set to daydream when it is connected to a power source.

Daydream doesn't trigger if Phone is switched off by button.

This was indeed my problem when I was testing Daydream mode. I didn't want to wait the three minutes for the screen to time out, so I kept pressing the power button. Testing went much better after I read your answer and changed my timeout to 15 seconds.

"if Phone is switched off" - should read: if the screen is switched off.

I had the same problem and found solution in configuration of Daydream. There is an option 'More' and then by default it is selected to start clock by docking. I've just changed it to 'both' docking and charging and that's it.
Hope it helps.

Daydream only woks when you let the phone turn off by itself. After you set the screen timeout to any time, let it shut off dont press the power button. That is why daydream wont work with the "keep screen turned on" option.


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Images in PDF File are distorted
I have a PDF file, when I open it on my computer (Linux) the Images in the PDF file is displayed properly  (Its sharp)
But when I copy the same PDF from the computer to Android device and opened it there,
It looks like this

What can be the reason for this image distortion. What is the difference in opening this in computer and Android?
Any suggestions can lead me to a better search.

PDF files are designed to maintain their content across platforms ,be immune to the application or OS
Hence, recommendation was to try alternate PDF app, which worked for OP. Adobe PDF reader used earlier was buggy, it looks like
Here's a list of PDF readers, thanks to izzy


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OnePlus 3: Unknown process 99041
I seem to have this odd app 99041 running in the background and I have no idea what it is. The fact that it doesn't even have a proper name makes me think it's a bit dodgy.
Any ideas?

I did do some searching before I posted this; I don't have an issue with battery usage as that process used up a mere 1%. My question was about the process itself and what it does, as I've never seen it before.

If it has no name but just "a number", it's usually some "native" system background process (the number is the "user ID"). You could find out more using adb shell or a terminal app, if you're not afraid of the command line – or using a process monitor app. A good choice here would be OS Monitor, which is available on F-Droid as well as on Google Play:

OS Monitor (source: Google Play; click images for larger variants)
Your candidate would find its equivalent in the process "149" (3rd line from the bottom) in the first screenshot. Being a "native binary", Android cannot find any information in its package list, and thus only gives an ID. First entry in the second screenshot shows what details you can additionally obtain on a process by using OS Monitor.


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Why does OK Google voice search unlock Moto G4 Plus?
So my phone (Marshmallow) was locked. I said Ok Google, to search something. It searched directly from the lockscreen and when I tapped home, it actually unlocked the phone.
Is it a security hole or something?
My phone is Moto G4 Plus

Trusted voice ("OK Google")

Trusted voice
When you say "Ok Google" from a secure lock screen and we're able to recognize your voice, you can ask Google to do things for you, or visit sites, without manually unlocking your device.
"OK Google" settings options (How to turn on/off OK Google and its settings (Trusted voice, etc)): Google Support

Source: Google

But another answer says that it's not accurate and hence not reliable. Is it so?

I think it's quite good to recognize a learned voice but it's not so reliable because not so hard to mimic another person's voice unless if he/she has a very uniqe one.

Yeah, anyways that's fine for me as I do not spend time around hackers etc  ;). So will keep it turned on. Thanks

@BálintBabics Actually, the research I've seen suggests that even voices that sound very similar appear quite different as a waveform -- giving lots of points to distinguish them via software.  A replay attack is more likely.

How does this work if you never use the voice functions? What does it intuit as the voice it should trust?

@SuperBiasedMan In order to activate this you have to repeat "Ok Google" thrice.

@ReeshabhRanjan There's no need for "hackers". a coworker could use his magical device (called smartphone) to record you when you say "Ok Google" and then just replay that to access your device...

@Bakuriu By 'hackers' I meant that only very geeky people will know this thing.

I would disable such a feature.

It is a feature as you can see in Lenovo forums

Long press on home screen and then press on settings.
Go to voice -> ok google detection and then turn off trusted voice.

Another post there says

Its not a bug. It just recognizes your voice but its not safe. As the feature is not accurate it may unlock even with others voice. Better turn off trusted voice. The voice command works even from lock screen works if your turn on option to Ok google from any app.

Bro you have the same answer, probably a better one. But why so many upvotes to the other one, who gave even wrote an answer after you?

It's part of smart lock as trusted voice. I'm using trusted location as my smart lock. Whenever I'm at home and office phone get unlocked automatically when pick it up. My home and office co ordinates are as trusted locations.
You can also use trusted devices, such as your fitbit, Bluetooth devices. Whenever you make phone contact with these devices phone get unlocked.
I liked this feature a lot, more convenient to unlock phone. But with caution. Keep backup security as pin or pattern.


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Dash charging on lower than rated voltage - possible?
My OnePlus 3 dash charger is rated 200-240V. I will be travelling to a 100V country and wondering
(a) If my dash charger can be plugged into a 100V socket without damaging it or the phone and
(b) Whether it will deliver Dash charging speeds.

Don't plug into any socket not rated for your adapter. Instead buy an additional 110V-220V converter.

Simple answer is No, it will not work the way it is supposed to, if it works
Any charger for that matter any electrical appliance can only deliver what is expected of it when it operates under the conditions it is designed for.
That is what standards are meant for and that is what makes it mandatory to be adhered to
Your charger work may work erratically charging normally but definitely not dash charge, while it may not damage the phone. Quite likely the charger won't even fit into the wall adapter there !
See this for more
Complete Guide to Using the Correct Charger or Power Adapter (and What Happens If You Don’t)
Even within standards, compatibility and ability to fast or dash charge is tricky at times as you can see from the table for one plus 2  from OEM site given the nature of dash or fast charging

So, how do I charge?: Use a power bank to charge your mobile, Googling should help you find one that is rated for 100 V. Quick search throws up one such power bank. It may be easier to request somebody in the place you are visiting to buy it for you


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How should I correctly turn on my phone?
This is regularly driving me nuts. Every once in a while, my phone freezes for whatever reason. I press and hold the power button to shut if off. Now comes the part that's giving me trouble.

If I just press the power button, nothing happens.
If I press and hold the power button, at some point a picture of a battery appears. It will disappear again after a while (probably because I'm still holding the power button and shutting the phone back off)
If I press and hold the power button and release it when the battery image appears, the image will stay and indicate that the battery is being loaded.
If I press and hold the power button for just the right amount of time, the Galaxy S2 logo appears and my phone boots.

So, usually I find myself going through this cycle a couple of times until I finally get my phone booted. What am I doing wrong?

I'm assuming you have a power cable plugged in.
In that case you'll have to unplug the cable, turn it on and plug it in as soon as something appears on the screen.
I've had this problem several times when trying to flash the phone while tethered to a computer and forgot to take out the USB cable when rebooting.

That seems to have been the whole source of the problem. If the phone is not plugged in, the Galaxy S2 logo will appear right away.


text:
Wipe before upgrading from stock nexus to CM?
Since CM is based on stock Android (AOSP), and the Nexus 7 is a stock device, can I just flash the CM zip without first doing a wipe/factory reset?
I just wonder if it's possible to avoid the hassle of backing up and restoring all my apps and settings, widgets, email settings, etc...

What you are describing is what's known as a "dirty flash" which is a no-no! Especially from AOSP to CM and vice-versa, could lead all sorts of force closes etc. Likewise, [a particular custom ROM (insert of your choice)] to another but different [custom ROM (insert of your choice)] and vice-versa.
The only time a dirty flash can be performed if going from CM nightly to the latest nightly, or [custom ROM] to a more recent version of same [custom ROM], theoretically, although no guarantees that everything will work "proper". Occasionally force-closes will be exhibited or some "weirdness" will manifest, hence no guarantees.
Really, if going from one ROM to another - best to wipe cache/data completely provided a backup has been done in the first place :)
Why not use a backup tool such as Titanium Backup or the basic backup tools found on the Play store in the event you are not rooted? :)

Yeah, I know. But it's still a huge effort, even with Titanium Backup. I'm very particular about my widgets and icons, and I never remember where they were. Plus I use app-specific passwords so I have to delete them all and re-generate them. It's really a pain in the ___ despite Titanium.

If you write down your app-specific passwords, they can be used again. I keep my app-specific password for my phone stored on the computer (mainly because there was a time when I was wiping quite often for testing and it was a pain to recreate the password every time). Definitely not the most secure, but the computer is secure enough that if someone were able to get in, access to my Google account is the last thing I'd be worried about.

Not recommended. You'll more than likely run into issues and just eventually have to wipe and reset anyway.


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What is the main activity of Google Keep called?
What is the launcher activity of Google Keep called?  I thought a short Google search would help, but apparently not.

The question How to launch Google Keep from shell? links a document which can help you to figure it out: activities are listed in the app's Manifest. I guess your intention is to start this activity from command line?

@Izzy but how do I see its manifest?  It's a binary file with little bits of text here and there.

See below -- I just summed it up and made it an anwer :)

How to find the activity?
Activities are listed in the .apk file's Manifest. This is e.g. explained in Run Android Application from Command Line. The linked page gives a short example:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
 package="com.iftitah.android.contact">
  <application android:icon="@drawable/icon">
   <activity class=".Contact" android:label="@string/app_name">
    <intent-filter>
    <action android:value="android.intent.action.MAIN" />
    <category android:value="android.intent.category.LAUNCHER" />
   </intent-filter>
  </activity>
 </application>
.
.
</manifest>

The activity is listed in the <activity> element, which also holds the intent to be called (in the contained <action> element).
How to investigate the Manifest?
Now for the tricky part, as we are no developers: How to view the Manifest? Luckily, we can get some help from the Playstore for this -- e.g. in the form of an app called App Detective:

App Detective and AppExplore (Source: Google Playstore; click images to enlarge)
As you can see in above screenshot, this app allows the user to investigate the Manifest files of installed apps, but does not stop at this. Ressources, libraries, signatures, and more can be looked up.
Alternatives worth mentioning are the ManifestViewer and the AppExplore. Pick your choice :)
So what is the main activity of Google Keep?
Using above "investigation methods", Kevin figured out it is com.google.android.keep.BrowserActivity (see below comment if you don't believe me ;)

Wow thanks!  Two questions though: How does it read the manifest?  Does it just know how to decode it, or does it just compile all the properties of the app into a manifest that is functionally the same as the original?  The second is: I can just load App Detective and Keep onto a JB emulator, right?

First: I don't know, but I'd say it decodes and reads it (no secret in the format). Second: I never used an Android emulator, but I'd say it should do, yes.

The AndroidManifest.xml is binary encoded on generation of the apk, the format of the binary version is "difficult" to analyze and parse, fortunately for Android, since the AOSP source is available, some took pain to read the original source to try reverse engineer it. After running tools like this on a binary encoded version, is not guaranteed to be identical to the one that the original developer used. :)

Which reminds me of: "Open Source" != "Fully Documented". Thanks for the insights, @t0mm13b!

@Izzy that's true.... for some reason, the encoding of the Manifest was done at the C++ level using very long-winded "code" that sorts of resembles peering inside a Microsoft Excel/Word document which is in a proprietary format! I suspect, its to keep down the overheads of including a bulky xml file or to obscure it... who knows :)

Yay!  I installed both Google Keep and App Detective on the emulator and it worked flawlessly!  In case you were wondering by any chance the launcher activity for Google Keep is com.google.android.keep.BrowserActivity.

Thank you for the feedback, @KevinOrr! That makes the answer complete -- so I compiled it into my text :)


text:
Was Firefox ever the default browser for Android?
Before I bought my Android, I heard that Firefox was its default browser. Upon noticing that this is not the case, I had assumed that the Internet browser on the Android was Google Chrome, but I just installed that today. Was Firefox ever the Android's default browser, and what is it now?

No it was never the default browser.

What's the current default browser? Feel free to post an answer so that I can best answer it.

I love when people -1 without a comment.

Firefox was never the default Android browser. The actual default browser is based on the open-source WebKit engine, which also powers the Safari browser on desktops, laptops and Apple's iOS-based mobile devices.
In the other hand, Chrome is based in Chromium and offers more options and performance than the stock browser.

You can read this similar post and here for some more information about the webkit choice by Android.

Chrome also uses WebKit.


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Create Defy Kernel Backup
I own a Motorola Defy and it is running 2.2.2.
I was wondering if i could create a backup of my kernel by any means!
Is there any software/application/method which can help me achieve this?
Thanks

Please see this previous "How to backup an Android device?" question http://android.stackexchange.com/questions/390/how-to-backup-an-android-device

As GAThrawn already indicated, the answer to your question is covered by How to backup an Android device?. As far as the kernel is concerned, two of the answers apply:

using adb pull to do a file system copy as described in this answer
create a Nandroid Backup from within your custom recovery as detailled in this answer

Both variants require your device to be rooted, and for the Nandroid backup you will need to have a custom recovery (e.g. ClockworkMod) installed.


text:
How do i use a lockscreen from another rom
I want to use only the lock screen from another rom for the same phone.
I own Micromax A52.
And I am using Xzoom v3 as my rom with Dark Angel theme.(to be precise if anyone knows and if it matters :P)
But i want to use the lock screen from another rom 'SuperStock52' which is also a rom for the same device.
How can i port that lock screen to my rom?

Unless the lock screen is some kind of 3rd party app (like GO Locker), then I believe you would have to modify the ROM yourself, and port the lock screen over manually, into your 'new' ROM. - In which case you might be better off asking for advice over at XDA, or another developer forum.
If it is some kind of 3rd party app, chances are you can download & install it from the Play store, or download the APK online from the developer's website.
EDIT: Rereading your question it's occured to me you might actually be asking how to port over the lock screen (IE: which files to modify in the ROM) - in which case, you should probably go to XDA (see above link) and ask for advice.


text:
Can't install Google Play Services
I just upgraded Google+ to 3.6.0.44338848 (released late March 2012) and now it won't launch. It says:

This app won't run without Google Play services, which are missing from your phone.

If I tap "Get Google Play services" I'm brought to Google Play where I tap "install" and "accept and download" but then I get "Error: No connection."
(I do have a connection. I can browse the web just fine.)
Now, I should mention that Market/Play has been odd the whole time, I've had this phone, a T-Mobile myTouch 4G running Android 2.2.1. Whenever I want to install an app, I have to go into Applications, tap Google Play Store, and tap "Uninstall updates" to restore the Market app. Then I can install applications. Over time, some process upgrades Market to Google Play but I can't install applications until I downgrade to Market to avoid the "Error: no connection" message. The processes is frustrating. On my old LG phone (also running 2.2 Google Play worked just fine).
I'm been putting up with all this downgrading because it's not often I install apps and usually there's no problem after installing or upgrading an app.
But now the Google+ app is unusable so I'm motivated to do something about the "No connection" problem.
I've read through posts such as http://www.teamandroid.com/2013/01/14/fix-google-play-store-no-connection-retry-error-message/ and Google's help page at How to access the Google Play Store app - Google Play Help but I'm stuck. Please help.

I was able to install Google Play Services by browsing to its page at https://play.google.com/store/apps/details?id=com.google.android.gms and then logging in, clicking install, and choosing my phone.
Come to think of it, I might start installing more apps this way, from the comfort of a desktop browser. :)
Anyway, I'm able to use the Google+ app again.
I'm still puzzled by the "No connection" business and having to periodically downgrade Play to Market to install anything from my phone running Android 2.2, but I'm glad I didn't have to root it and install CyanogenMod as suggested by some friends.


text:
What are these Two icons?
I was re-ordering objects on the quick settings When I noticed two icons that I do not recognise:

To clarify, it's HotKnot and BroadCastTile That I am questioning.
Whats odder is that they are not in the Quick settings menu (Even if I add them)

What are they for, and how can I use them?

HotKnot - The technology allows the capacitive touchscreens of smartphones to interact – a feature that can be used for quick data transfer/sharing, in a similar way to NFC.
Source: link
BroadCastTile - It is just a customizable tile, you can add a custom tile if you know the constraints.
Source: link

HotKnot is a kind of wireless communication like Bluetooth or NFC.
BroadcastTile is for creating your custom Quick Setting. See here.

Not audio profiles, the Android bot shaped one.

I edited my answer.


text:
What lock/unlock button does on recent apps screen?
On recent apps screen there is a lock/unlock button on each and every app, I want to know what's it's function. I am attaching screenshot for reference.

It's Marshmallow.

If you lock an app in recents and click on tap to clear, it will stay in recents. Apps not locked will be cleared (that kills all the running apps without the need to kill each one separately)

I thought the same, but after you answer I realized it's bit different behaviour wise. The moment you lock an app and press the clear button, it clears all the app at that moment but when next time you press the recent apps button you will find locked app there. Cheers!

Exactly. It is to ensure that locked apps are always kept alive


text:
Nexus 6 Powered On Strangely
Earlier today, when trying to power on my Nexus 6, I had a strange thing happen. I normally power on my phone when it is still plugged in to the charger, and I tried doing that today, but after holding in the button for several seconds, the phone did not start to power on as it normally does. I tried unplugging the phone from the charger and powering it on again, but still nothing. When I plugged the phone back in to the charger, the phone began to power on immediately, but not before the hidden notification light turned green for a second. After the phone finished booting up, I got a low battery warning, as my battery was 8%, even though it was at 75% last night when I plugged it in.
Does anybody have any idea what could have caused this? To make sure that everything was working properly, I turned the phone off and on again without it being plugged in to the charger, and everything seems to be working fine, but I am curious about what happened. I am running the latest version of Android Marshmallow available for the Nexus 6 (build number MMB29Q), and the device is not rooted.

Is everything working as expected at the moment?

@Rexford Yes, everything is fine.

@beeshyams I've only had the phone since August, and this is the first time this has happened. I have since charged the phone to a full 100%.

Since you have confirmed that the battery is just six months old, I am guessing that this is a different problem
Nexus and HTC phones seem to have an issue with battery reading showing incorrectly and have a method for battery reset logic. This method varies between various models and googling for "Nexus 6 battery reset logic" led me to this method suggested by Claire LP. The problems described in that thread are not the same as yours but if your problem is related to resetting logic, it may help:

Power off your phone.
Press and hold the Power and Volume Down buttons. This will put the phone in fastboot.
Use the Volume buttons to scroll through the menu until you see "Bootloader logs"
Press and hold the power key for a long time (7+ seconds) until the phone reboots.

Thank you! If I ever run in to this problem again, I will try this.

Glad to help :)


text:
Network usage : How to monitor by time
I'm looking for a way that tracks network usage by type. I'd like something that at the end of the day says "8h 20min on 3G, 3h under WiFi network".
I've searched a lot but didn't find anything (there are tons of apps that tracks megabytes exchanged, but this is not my interest).
Is there a technical problem behind (i.e. lack of system APIs)?

App recommendations are off topic and is reason for closure. Since you have also awarded a bounty for it , I have taken the liberty of editing your question to avoid specific app recommendations. If that is not agreeable, please roll back to the original version

@Surfer on the fall, you could try https://softwarerecs.stackexchange.com/ If you are looking for a specific app recommendation...

I don't think there is a technical difficulty in gathering such information. Lack of such apps is likely because of lack of demand. For an average user, it is not the time that is important but the data used while on a plan or roaming and hence an abundance of such apps
I am not aware if the information you seek can be pulled from Android OS requiring programming skill . There is an open source app Network Monitor, which can help you. It doesn't directly give you what you want, but information can easily be extracted.  App has been updated last month. Extract from app description:

Network Monitor is a diagnostic tool which periodically tests your network connection and logs the results to a database on the phone....It also logs other information about your device and connection status, such as:
  The network type (WiFi, mobile/EDGE, mobile/HSPA, etc)

It offers a rich selection of features to log and display. This solution shows minimum settings required to achieve your goal :

Network Settings →  Enable Service ( Enable / disable as required per duration of monitoring)
Network Settings →  Log frequency can be varied from 1/2 sec to 1 hour , depending on the accuracy you need
Advanced Options → Fields to monitor - offers 50 + fields. Basic fields needed would be :

Timestamp
Network Type
Is connected

You can view the log file with these settings as shown in the screenshot below

Log file can be exported ( mail it yourself) in several formats (Excel, CSV, HTML, KML, Gnuplot the raw database) , for further analysis. Excel would be the obvious choice.

You can filter the Network Type and Is connected =1 ( to avoid disconnected times ), say for WiFi
Use the count function of Excel and multiply it with log frequency ( i.e, time) to arrive at total time and convert it to hh:mm format  - my Excel is rusty, there should be better ways :)
Repeat for mobile data


text:
Is battery consumption linear?
I am benchmarking an app using the batteryhistorian.
The result is a chart where every percentile is a "tick".
After I've measured the battery consumption
and let the battery drain to half, I would like to be able to save time
by making  a change and restarting a measurment without having charged
the deviced back to full.
Is it a fair approximation to assume that a drop from 85% to 84% is the same
as a drop from say 64% to 63% when benchmarking an application?

Li Ion battery discharge is not strictly linear, (unlike a capacitor ). This ensures available power is utilised till the end of battery charge

But it is fairly linear, more so at lower loads as can be seen from this figure, where C-rate or charge rate is the discharge/ charge rate

Assuming your app is not a heavy power hog, it is reasonable to extraploate discharge. But, since the discharge isn't strictly linear, it would give better results if

Battery drop interval is more , say 5 to 10% and not 1% as proposed
Battery drop is not measured below 30% of battery ( to avoid greying into non linear portion of curve)
Measuring at 1% drop inherently introduces rounding off errors- if your phone has two digit accuracy, anything between 75.90 to 75.99 would show 76% . In the worst case, the error could be doubled (it won't fall to 75% till it goes below 75.90). Which means a 20% error, and that can be reduced to 2% over a 10% drop
Avoid measuring when the battery is fully charged to reduce errors. Measure at about 85% for the first reading and around 50% (or higher ) for second reading after tweaking your app


text:
Enable /system write in TWRP - Systemless root
Moto X Play (XT1562), SuperSU 2.78 (systemless root), TWRP 3.0.2-r3

When I flashed TWRP, I chose the option of not writing to system to enable OS update (and also made a Nandroid just after flashing it as a backup)
Now, I made some minor changes to system audio files, without dwelling on consequences -  won't be able to update OS ( update expected this quarter) without flashing stock OS

I want to enable /system write option in TWRP ( without flashing TWRP again ) so that :
a) Flash backup Nandroid ( of stock OS from the first Nandroid), if I decide to upgrade OS
b) If I don't want to upgrade, have a complete Nandroid and tweak further knowing that I can safely roll back changes
In other words be able to backup and restore /system along with data
Is it possible and how ( please provide detailed instructions )?
Edit: Flashing different versions didn't help - see my unanswered post on XDA

If you wanted to reset TWRP's configuration (and thus be able to access the wizard again), you could simply delete the .twrps file under /sdcard/TWRP/.

@DeathMaskSalesman: Thanks I don't find that file - this is a modded TWRP

I found a workaround, as you can read in the answer below.

It appears that the issue was TWRP's fault. To make the /system partition writeable, one could:

Uncheck the checkbox near Mount system partition read-only, in the Mount section of TWRP (screenshot at the end of this answer);
Delete, move or rename the .twrps file to force TWRP's setup wizard to trigger, in order to make /system writeable. This file is located under sdcard/TWRP, and can be managed directly from TWRP's File Manager, accessible from the Advanced section of the recovery. Notice that any TWRP setting customization aside of themes will be reverted.

Let us continue this discussion in chat.


text:
Home button or back button to leave an app?
Is there a difference between leaving an app by pressing the "back" button vs. pressing the "home" button?
I've got an app which includes a countdown timer. The app says it will notify me when the timer reaches zero but only if the app is minimized (home button) and not if it's closed (back button). Is there really a difference here?
Note that I've confirmed that the app stays available in the list of running apps (the "history" button, or whatever it's called) regardless whether I use "back" or "home" so I am confused. Has the developer misunderstood this?
Details: I'm running the app Ingress Portals on a stock Nexus 4.

A quick note about the "list of running apps": it's not a list of running apps, it's a list of recent apps. Having an app in that list doesn't mean it's running, and you don't need to remove apps from the list to "save battery" or "save memory". Conversely, an app could be running a Service and not be in the list at all.

In general, when you leave an app with home, or by launching another app from the recents menu, Android keeps the state of the app around for a while. That includes the stack of which screens you've looked at, the position of scrolling things, selected items, the state of checkboxes and the text in text fields, and other such things. It'll only discard that state if the device runs low on memory, or if you don't come back to the app for a long time.
If you instead press back, it takes the current screen off that stack, throws away that state, and goes to the screen you were looking at before. Repeated back presses keep doing this until you're all the way out of the app, and it has no state left. (Note that this is only the state of the screen as I described above. The app ought to save any persistent state, such as the document you were editing, or your high score.)
As Sachin Shekhar says, use home if you want to come back to the app in the same state; or back if you are done with the app and you want to see the main screen or starting screen next time you start it. In addition, note that apps can change the behaviour of the back button (such as how web browsers usually make it go "back" in the browser instead of leaving the browser completely), but they can't change the behaviour of the home button. You can always use home to get out of a misbehaving app.
There's one more thing. Android also allows apps to create what it calls a Service. This is a part of the app that runs in the background, with no visible part (unless it sends notifications). Any app that has a long-running task to perform, such as a download manager, or a torrent client, should use a Service so that the download keeps going even if the app isn't on your screen. It should make sure the Service exits when all downloads are finished, so you don't need to worry about how to exit it.
Perhaps this app is using a Service to run the countdown, and it has changed the behaviour of the back button so that as well as leaving the app, it also stops the Service. That could be why you get that instruction. But it's only that way because the author chose to do it that way: he could just as easily enable and disable the countdown with a checkbox or button inside the app. It's not standard behaviour, and in general, you shouldn't expect to have to use home to keep downloads or long-running tasks running.

Generally, Back button calls onDestroy() method of current activity. But, Home button pauses the activity. This is the difference if a developer follows standard guidelines (a developer can choose not to respect this behavior).
In layman's term, when you exit app with Back button and start it again from Recent Apps list, it'd be app's fresh launch. And, when you exit app with Home button and start it again from Recent Apps list, the app would be resumed from where it was left. It means that Back button kills an app whereas Home button sends an app to background (Android memory manager can still choose to kill it if system runs out of memory).
The app in the question is simply showing standard behavior.

What a difference! That is absolutely not clear to me as an average user. So you're saying I should not use back, except to dismiss a menu or similar.

@Torben You can use Back button to exit the app if current session isn't important to you. If you just want to pause the session or you want to run app in background while using another app, use Home button.

@Torben Example: Let's say there's a torrent download client following standard behavior. If you want to stop the download (to save battery and/or internet congestion), use Back button. And, if you want the app to continue the downloading while you read an ebook or surf the web, use Home button. Its not that hard to understand (think about multitasking of PCs).

I'm not saying that it's hard to understand -- it's just that it's absolutely not evident from simply using the phone. Now that I know, it's easy enough to remember, but from a user perspective, there doesn't appear to be any difference unless you deliberately try it out (but even then you would still need a hunch about what you're going to test for).


text:
I'm seeing duplicated images and videos on Gallery
I'm facing a strange situation on my Nexus 4, with Android version 4.2.2. I've being using it for the past 2 months without any issues whatsoever (other than a "regular" battery performance), but since last week I started seeing some duplicated albums with images on the Gallery. So, some images and videos appear twice, both with the same album name, but on a different "physical" folder, one on the folder /storage/emulated/0/ and the other on /storage/emulated/legacy/. I'm absolutely positive that this issue started only last week and the "duplicated" images existed before this issue ever appeared. I haven't installed any custom ROMs, I'm not rooted and haven't installed any apps in the las week (other than Google Translate, but I find it hard to believe that this is related). If this is a duplicated, please feel free to close it and point me to that discussion. If you need any more details, I'll update my question.

That's not duplicates. If you are the "device owner", /storage/emulated/0/ is your storage area (where your files etc. reside). /storage/emulated/legacy/ is a symbolic link, always pointing to the logged-in user's storage. That is, if you are the device owner, and you are logged in, both locations are identical. If some apps show the contained files as "dupes", they obviously have problems interpreting symlinks.
While for the gallery, this sounds pretty strange (if we are talking about the stock gallery, and not a 3rd party app): the very same Android developers who designed the multi-user capabilities should have been aware of that. Still, this is not the first time I heard about it. I cannot find the other issue currently, but a solution is as follows:
Go to Settings→Apps→Manage Apps, and scroll to the Gallery app. Open its entry, tap "Clear Cache" and "Delete Data". Tap the back key, and repeat the same for the "Media Storage" app.
Don't be afraid about losing data: the Media Scanner will re-collect them at its next run. You can trigger the scan by either...

powering off/on the device (bah!)
going to Settings→Storage and safely remove the SDCard, then mount it again (OK for one-time use :)
using a helper app like e.g. SDrescan or Rescan SD Card! (if you need it more often)

Once the Media Scanner is finished, all your media should re-appear in the Gallery app. Hopefully without the "dupes" :)

I understand the they are not actually duplicated, I had seen it like that on some file explorer apps; but, in fact, I am now seeing them twice on the stock gallery app, wich had never happened before and is quite annoying.

I've read before that the stock gallery sometimes did things like that (just remember that now). I cannot find the issue currently, but it was exactly the same thing with the storage being linked. If I remember correctly, the solution was to delete chache & data from the corresponding apps (gallery, media-stuff -- don't remember the exact places), as the media-scanner then refreshes them fine.

I couldn't find a solution for this exact issue either, wich is why I posted a question here :-). I'll try deleting cache now and will let you know if this fixed the issue. Many thanks

You're welcome! If cache alone doesn't help, try deleting data as well (I guess you'll have to). As said, the media scanner should re-collect it again at its next scan (unmount/remount SDCard to trigger it). Unless, of course, you delete data from other (unrelated) apps ;)

It worked. I had to delete the data + cache (deleting cache only wasn't enough). Thank you very much, I'll accept this answer, but can you add that comment on the body of the answer?.

I certainly will, thanks for the feedback! Would you please let me know where you deleted it from? Just the gallery app?

I deleted cache + data from both the "Gallery" app and "Media Storage" (though I tested deleting them both, not one at a time).

Yupp, exactly. I just remembered it was a combination in the other case as well. Seems to fit. Thank you again for your feedback -- I will include this now with my answer. Glad we could solve it!

Yup, as I said, it was quite annoying seeing those duplicates there. Thank you very much for helping me.

Hello @Izzy. I have this problem constantly reoccurring. Why is that?

@Boris_yo "constantly reoccuring" after having applied above "fix"? And with exactly the described locations? Then the only explanation I could offer is a buggy media scanner. No idea how to fix that (apart from a software-update, if available, which might fix it).


text:
Warranty on Nexus 7
I just won an auction on the Nexus 7. The seller claims that he doens't have the original sales receipt but says I will be able to sign up for the warranty online with the registration & activation of the Nexus. So, how does this exactly work and will this warranty be of the international type?
Thanks!

You need to contact ASUS directly.
Google play's support page says:

Nexus 7 limited warranty
  The Nexus 7 is manufactured by ASUSTeK Computer Inc. ASUS provides a limited 12 month warranty for the Nexus 7. Please refer to the warranty card in the Nexus 7 packaging or review ASUS' limited warranty details.
If your Nexus 7 was purchased from Google Play, please contact Google
  customer support for service on the ASUS limited 12 month warranty. If
  your Nexus 7 wasn't purchased from Google Play or you're looking for
  out of warranty repair service, please contact ASUS directly.


text:
Preventing charging while USB debugging - One X
I am often using my device to develop, so I'm a little bit worried that the constant charging might fry the battery. Is there anyway to use USB debugging while not charging the phone?

I know many phones that complain the charger should be unplugged. I wonder why they don't have an electronic switch that takes care of this.

No need to worry. Constant charging won't harm the modern batteries.

As far as I know, batteries won't fry on constant charging. They chips in them that control overcharging and low charge. So they won't die easyly. I am using my desire just like you explained for almost 2 years and it is just like the first day, I need to charge it every day :)

It's an hardware issue that is easy to fix: charging is done with the USB cable. My answer is to cut the wire of the USB cable. Or more simply, you can "cut" the courant by placing a tape or any other non conducting material on the appropriate pin.
The spec of USB are easy to find, eg http://www.kineteka.com/microusb-b.aspx

I wouldn't worry about it.  Lithium Ion batteries used in most (all?) modern phones are not as sensitive to "top-off" charging as NiCd batteries, which have "memory" and stop accepting a full charge.   Searching "lithium ion battery" on this site will bring up many discussions, such as this one.


text:
Why won't my nexus 7 update to Jelly Bean 4.2?
I was notified that there was a system update, but when I applied it the tablet was still on the older version of Jelly Bean. I've even done a factory reset and tried again, but no luck. Are there any logs that I can look at to track down the problem?

Have you tried over WiFi, or just 3G/4G?

Can you use computer for update?

I've done this over WiFi. How do I use a computer for the update?

Have you rooted your nexus 7?

It is not rooted.  It failed pretty much straight out of the box (I bought it last week).

This turned out to be a hardware issue. I had two relatively pleasant conversations with tech support at google play and asus. Since it was a new purchase I just returned it.

Before updating make full backup of your data.
For update using computer you just need to flash system partition using fastbootfastboot flash system system.img, where system img available at image-nakasi-jop40c.zip available inside nakasi-jop40c-factory-6aabb391.tgz, what you can download from Google Nexus factory images page.
Using scripts from tgz archive will erase your data without prompt!
Dont't flash data, even as you got bootloop (it can be, if you has applications, incompartible with new version of firmware).


text:
play.google.com and Google Play app out of sync
Having become fed up with a custom ROM i was using, I reverted back to a previous ROM via a nandroid backup (through CWM Touch).
It would appear that the backup preserved all my installed apps and data (Was under the impression they didn't, so this surprised me somewhat), but since then the 'My Apps' listing on the google play website has been out of sync with what is actually on my phone. I also seem unable to request (un)installation through the web interface.
Help would be muchly appreciated.

Did you check that your Google Account is still linked in Settings > Accounts and Sync?

Yep, i I tried removing the account,  then adding it back through the play store, to no avail.

It may be the link to the Play store was lost. I think if you install an app from, say, the amazon app store, Google Play will not be able to update or uninstall it, as the link is gone. Similarly, restoring an app from a previous rom backup may not create that link.
Titanium Backup can recreate the links (the free version can can't do this). Or you could uninstall the app and try installing it fresh from Google Play.

Where would I find the option? All the references to relinking apps on the android market/google play that i've managed to find required the donate/pro edition.
(I'm probably looking in the wrong place)

Not to worry. Ended up buying a TiBu PRO key anyway. Market Doctor fixe it up perfectly, thanks.

Sorry, it looks like you're right. The re-linking requires the Pro version. I was looking in the summary of the app and it implies it is in the free version as well. Glad you got your problem fixed!


text:
Sync ext SD to USB OTG **without** using a PC
Device Details

Moto X Play - Android 6.0.1, Rooted (Systemless root)
Samsung 64 GB ext SD
San Disk 128 GB USB - came shipped with FAT 32 reformatted to exFAT since I have folders > 4 GB on external SD

Use Case
Sync entire contents of ext SD to USB (one way sync without deletion of SD card contents ) on weekly schedule / on demand , as incremental backup without using a PC ( I do have one but reasons for not wanting to use it are not relevant)
Other Details

USB drive recognised by device correctly connected by standard OTG (Settings → Storage & USB )
Busybox installed . It came bundled with ROM Toolbox Pro. I haven't used it directly. If another busy box is to be installed, it's fine as long it doesn't clash
Mount points as below

Things tried

Unsuccessful app search- I wasn't able to find an app that can do this (Folder Sync claims to but it can't see USB)
Googling for alternatives
MacroDroid automation fails, since app can't see USB (raised this in app forum)

Question: How can I do this ? I am open to any means
Please note that I intend placing a bounty of 100 , any answer meeting needs before I post bounty will be awarded similarly (I may delay posting the bounty to ensure I get a solution)
Please avoid solutions that

are not tested - it should have been tested on your device and USB configuration to give it credibility
Involve PC , uploading to cloud, transferring to remote server etc
References to claims from doubtful sources which can't be verified
Involving use of File Managers ( I had mixed results with these but then that is for another question)

Aim of the above is not to deter solutions but to discourage frivolous attempts. If clarity is needed, please ask
I discussed this need on chat and some potential candidates for solution included BusyBox, rsync and Tasker. I know nothing of these means so Please do provide complete details. Being a bounty question (almost), I expect that I should be able to straightaway implement successfully without seeking clarifications.
( Being a rooted device with systemless root, solutions using root are fine. However, if OS is to be modified on any way, please highlight as systemless doesn't permit it, though there is a work around )
I am strapped for time and need to get this working ASAP

I'LL see if I can work on something When I can :)

Ah,  Fair Enough :) Hadn't Checked the Chat.

As we figured out the solution you now use in chat, this answer should comply with "being tested", "not involving a PC or file manager" and "relying on verified sources". Though in the meantime there was another rsync answer posted, you've asked me to present our solution as well – so here we go:
The rsync command can be used to accomplish that. Taken all your requirements into account (including those mentioned later in chat), the command line would look like this:
rsync -a --delete /mnt/sdcard /mnt/usb

Explanations on the command:

rsync obviously is the executable/command
-a stands for "archive", i.e. keep all attributes. This includes to recursively copying contents (directories, subdirectories, files), keeping filestamps and ownership (the latter usually requires root), preserve permissions, etc. For details, please refer to What is archive mode in rsync? on our sister-site.
--delete takes care to remove files on the target (here: /mnt/usb) which are not/no-longer available at the source (here: /mnt/sdcard)
remaining parameters specify the source to copy from (/mnt/sdcard) and the target to copy to (/mnt/usb). Note that we specified both as directories, so all content, also hidden files, should be included as well (the latter wouldn't if we had used a mask like /mnt/sdcard/*).
Note: make sure to specify the real mount points or at least real directories here (e.g. not the /mnt/sdcard symlink as in the example), or it might just copy the symlink over and think that's all you wanted :)

You might wish to try the above on a small source first to see how it works.

Now that the "how" is covered, question remains: Where is rsync? It usually doesn't come pre-installed on the device, and most Busyboxes seem to not include it either. There once was an app on Playstore called rsync backup for Android, but it's no longer there. As this wiki points out, you can directly download the rsync binary from here¹, then push it to your Android device, and install it. Assuming you've pushed the binary to /mnt/sdcard:
su
mount -o remount,rw /system
cd /system/xbin
cp /mnt/sdcard/rsync .
chmod 755 /system/xbin/rsync
chown root.shell /system/xbin/rsync
mount -o remount,ro /system

The above should be done either in a terminal app or via adb shell.
That done, and successfully tested from a shell prompt, remains the question of automation. I know that tasker can execute shell commands as root (in the past this was done by simply prefix them with an exclamation mark, today there might even be a checkbox for it – I didn't check that for a while), but your Macrodroid might provide that as well. Alternatively, you can do it the Unix/Linux way and utilize Cron, which is provided by Busybox; for details please see: How to use crontab in Android?

Also see:

How to use rsync over USB on Android with adb
the rsync man page for further details on available parameters and possibilities
How to rsync to android (in case you want to advance this to include your Linux machine ;)
RSync is also available on other operating systems, see e.g. this list on Wikipedia
there's another RSync app on Playstore: Acrosync – but it wasn't updated since 2013 and neither is it well rated (2.7 stars at 82 votes)
Backup your Android phone with Rsync describes a similar approach as above, involving different resources
How to automate command line when specific application is launched? (for on-demand syncing; note that e.g. tasker also allows to create widgets for tasks, which then can be "tapped on demand" to execute it)

¹ Of course you can also try to find the original app on sites like APKMirror or ApkPure, or download the app from here – but then you had to first install that app, and afterwards grab the binary from it's data directory /data/data/eu.kowalczuk.rsync4android/files/rsync – which I find a bit inconvenient ;)

Thank you, the solution worked fine for me. A couple of points that may help the readers : 1. I tried with all Busybox versions, which are well rated and none of them have rsync available the pro version of  this ( I mailed developer requesting him to add it), so that leaves with no choice but other means ( incidentally couldn't find the app on reputed sites mentioned ) 2. Automating the execution of command on demand / schedule   successful. Instructions here

TWRP could see the backup on USB , so presumably it should execute fine 4. Same with TiBu , though this requires a bit of workaround (Backup folder location > Storage Provider, click on that and choose options per your OS Version) 5. Though you are not a windows user, for the sake of completeness, you may consider adding extension of rsync on windows as well, as you did for Linux- I did see references. Will add more later if it can help readers

@beeshyams http://ptspts.blogspot.com/2015/03/how-to-use-rsync-over-adb-on-android.html has instructions on where  you can find and manually install rsync for Android. You'll have to be a little creative since you don't want to use a PC. I'd recommend trying to use webget and Root Explorer to download, rename, set +x, and move the binary.

@ChrisOlin: Thanks and I had seen that earlier, but not being familiar with Linux, did it the awkward way of downloading the app and extracting  rsync and shared it with Izzy and he included that in his answer., In foot notes.  Doing it can be learnt, but at a later time, when time permits.

Update : Verified TWRP and it restores fine from OTG. TiBu runs into problems. It sees the copied folder on USB but unable to select for restore. However, if I create a new Backup folder on USB , it restores.  In case of extSD being replaced, I suppose copying the backed up folder should work since all attributes and permissions are intact

@beeshyams Are you using DocumentProvider storage? If you are and it's still not working, SELinux might be preventing Titanium Backup from reading media from the flash drive.

@ChrisOlin: unfortunately, that isn't the case. Just rechecked it is Permissive .  Seeing mixed reports on net, works for some, didn't for others. Not sure why

@ChrisOlin: Besides, as mentioned I can create and backup from a new Backup folder , so read/ write access is not the problem

SELinux contexts are configured a bit differently than traditional Unix file permissions. I've encountered that exact issue with SELinux preventing Titanium Backup from accessing backup data and causing exactly the same issue you're describing.

Be forewarned. I'm not going to provide you with complete details, mainly because what you're asking for is so unspecific and obnoxious that the bounty on this question isn't worth spending the time to test a solution for you that I have no way to guarantee will work on your device. You can either ignore my advice and suffer or reason out any difficulties through critical reasoning and Google. If you don't like these options, you can always go buy an iPhone. They're designed for people that want something that "just works". If you can't spare the time to research or tweak a solution to work for you, Android may not be for you.
There are a variety of ways to accomplish what you're trying to do. Arguably, the easiest and most reliable method is using software found on most Android devices by default, which is what I'm going to focus on. Since you're trying to run something on a regular schedule, I would say the best solution would be to use cron. On that note, take a look at this StackOverflow thread since it's specific to running it on Android. Also, so we're all on the same page, cron is a job scheduler available on most (all?) Unix-like operating systems, which includes Android. Since you didn't go in to detail on when exactly you want this job to kick off weekly, I'll leave it to you to configure the crontab (which is well-documented on the internet and isn't difficult).
This will take care of scheduling everything, but the next step is to figure out how you want to back up everything, which is a very important question you were painfully unclear about. Do you simply want to copy new/modified data on the external SD card to the flash drive or do you want full backups of the SD card stored by date on the flash drive? These are questions you need to figure out for yourself before you ask the internet for advice.
Without knowing what exactly you're trying to accomplish here, I'm going to assume the first scenario works best. Since you're copying file level data (opposed to block level), rsync is probably your best choice here. It's very versatile and should work straight out of the box without needing to be configured. You should already have it available and if you don't, it's easily obtained through Busybox.
Assuming the mount points stay the same, the command I would use to accomplish this would be: rsync -rlpt /mnt/media_rw/0000-0000 /mnt/media_rw/E82C-B290. For your convenience, I've included a primer on the flags I used below:

-r, --recursive recurse into directories
-l, --links copy symlinks as symlinks
-p, --perms preserve permissions
-t, --times preserve modification times

There's also the -a flag (short for archive mode), but it does a bunch of other needless crap in this situation like syncing uid/gid. In most backup scenarios, using -a would make sense since you would want to preserve ownership if you have to restore from your backups. However, external SD storage uses FAT for its filesystem, which doesn't support Unix file permissions. While files on your external SD card do have an owner/group set, they're statically set by the operating system. If you try changing them, I'm pretty sure you'll get an error or it'll silently fail in the background. The flags I used make this process much more efficient, but if for some reason you want rsync to sync all that extra stuff, use the archive mode flag instead.
So, now that we have the command you need to run, it's just a matter of configuring the crontab and having it execute that rsync command. This isn't a very elegant solution, but it will work. If you wanted to set up some sort of logging (Mike Rubel has done a lot of work you could draw inspiration from), you could write a shell script, put it on your phone's internal storage, and have cron run the shell script instead of the rsync command.
To back everything up manually outside of cron, you can run that rsync command using ConnectBot or any other app that gives you shell access. If you plan on doing that often, it might be faster to put the command in a file (e.g. backupsd), chmod +x it, and stick it in a folder that's also in the system path (like /system/bin). This way, you can type backupsd instead of rsync -rlpt /mnt/media_rw/0000-0000 /mnt/media_rw/E82C-B290.

That was basically the solution I worked out with the OP in chat :) Just one side-note: instead of -rlpt, simply use -a (archive mode), that implies all the other switches :)

I addressed why I didn't use -a immediately following the summary of the flags I used and left it for the OP to decide. Clearly, great minds think alike.

Ah, sorry Chris, I missed that part. But to me, syncing UID/GID is an essential part, for ownership is relevant so the owners can deal with it correctly. Guess you play on the fact that though being true, that doesn't affect the SDCard due to FAT, which I agree to :) You might have wanted to point out your reasons in your post, though :)

You make a good point. I didn't state specifically why it's pointless. I'll edit and clarify.

wtf with the paragraph rant at the beginning?


text:
Why is the SD card mounted as read-only on PC when shared from HTC Desire HD via USB?
I just discovered that the SD card is now read-only when I use "disk drive" connection on the phone.
Why do I have to do in order to be able to write on the SD card from the PC?
I mention that the phone is rooted and is using the latest version of 2.3 available for HTC Desire HD (original rom).

It may sound really strange but the real issue was the corporate policy of mounting the the unencrypted drives as read-only. This is specific to BitLocker and there is a registry workaround available.

From what i have found on the internets is that there are a lot of people that have had issues like this with the Desire HD.
They all said that either formatting the sdcard in Windows, or even using Windows 7 to "Verify Errors" solved the issue.
Before you format, you can copy all the content off the sdcard, and then place it back after formatting.


text:
Folder or Folder Shortcut on Honeycomb 3.1 home screen
I have a Toshiba Thrive and want to have access to several files in a folder, but can not figure out how to do that without going through the effort of using File Manager?  Is there a way to do create a shortcut like you can do in Windows desktop?

ASTRO File Manager can help you with this, just install it and run it once, then you can add folders by long-pressing the desktop, selecting More and tapping ASTRO. It will let you browse folders and one can be selected by long-pressing it.


text:
Will using my phone whilst charging make it charge slower?
Just the question in the title.  If I have my phone plugged in and charging, will it take any longer to get up to 100% charge if I'm using it or will this make no difference?   (I'm using a galaxy nexus)

Yes.  The Galaxy Nexus will accept no more than 4.5W of power (0.9A @ 5V) from a charger, regardless of what the charger is capable of supplying.
This isn't a whole lot, so doing stuff will cut down on the amount of power available to charge the battery and it's actually possible to run down the battery while you're plugged in.  Testing by a guy on reddit showed peak power draws from the battery of over 5W when using google maps, so you'd end up using the entire charger supply to power the hardware, and another 0.5W drawn from the battery.

I can verify being able to use more power than I'm able to draw. While out driving around playing Ingress, even with the phone plugged into my car charger, between the app, GPS, mobile data, and the screen, my battery charge level still went down. (And it got damn hot, too.)

Yes, it will take longer to charge if you're using it. The same as when you're using a laptop while it's charging.


text:
search somebody from contacts with the numpads
My old phone Motorola Defy had the option by calling to search for a contact just typing a number. Not sure how that feature is called but I'll give an example:
If I want to call "Alex" i need to press 2(a bc) 5(jk l) 3(d e f) 9(w x yz) and I press the call button.
Now I got the Nexus 4 and there is not such a feature, which is really annoying. Is there a custom dialer that support this feature? Or is it possible to enable it from somewhere?

There is no way to do this with the stock dialer. There are a number of apps that you can install that do support this. Search the play store for 't9 dialer' (or click here). Pick one that you like the look of :)


text:
Is there a reliable way to detect the app responsible for an Airpush ad?
I noticed the other day that my Xoom's notification bar has started receiving Airpush ads (which is what it sounds like - push notifications that are really ads). I'm rather philosophically opposed to the idea of push-ads on my device, so I'd like to remove the offending application, but the ad doesn't give you any way to figure this out. Clicking on the notification star only gives you a link to the advertisement page, and nothing more.
I found Airpush Detector in the Market, but it doesn't seem to work on my Xoom, perhaps because of some Android 3.x differences. When I launch the app it says that no Airpush apps were found, but this is obviously not correct. Another option I've seen is systematically freezing apps using Titanium Backup until I find the guilty one, but that would be very time consuming and I'm not even sure if it would work.
I'm also aware of the permanent opt-out app in the Market, but I really would rather uninstall the app responsible for the ads (again, due to philosophical beliefs).
Is there any way for me to detect the origin of an Airpush ad?

Two points,
Firstly if you just want to stop getting the AirPush ads, AirPush themselves offer two ways that you can opt your device out of receiving the ads. Either:

Install the AirPush Permanent Opt-out app,
or visit their opt-out page and follow the instructions to enter your IMEI to be opted out.

Secondly I don't think that AirPush is the only game in town doing this. I uninstalled an app a few months ago when I tracked down that it was the one spamming my notification bar. Its ads didn't look like AirPush's and it didn't show up with an AirPush detector. Didn't track down who was providing the ads framework the app was using, I was just happy to get that rubbish off my device, for an app I only opened once a month or so I didn't need that hassle. It may be that these aren't AirPush ads, but one of their competitors. That app I just tracked down by working out which apps I'd installed/updated recently, then glancing through the Market comments to see which one was full of users screaming to get rid of the notification ads.

I suppose this is a good point, I didn't really consider the fact that it might not actually be Airpush. It definitely looked like it was, though, based on what I've read about Airpush (same icon, about once per day and such). Do you know the names of any other push ad frameworks offhand? I'm trying to perform a more generic search but I'm mostly just getting pointed back to Airpush.

@elder I wasn't getting the star icon on each one that you seem to with AirPush. Sorry don't know which framework it was, I was just happy I'd found the culprit and got rid of it, it wasn't an app I used often enough to investigate any further, looking at it they've since removed the push ads.

Install the Airpush detector app.  This will (in most cases) detect the app responsible.

As I noted in my question, this app did not find anything on my Xoom, but I was still receiving Airpush ads.

Touch the stars at the top of your phone and slide it down with your finger to view the ad.  Dont open the ad but instead put your finger on it and press and hold it down for 7 seconds and the app thats sending you the add will appear...................delete the app and the stars will go away.  My stars came from downloading the ringtone ( Fart) with my saMsung Galaxy Note 2 .


text:
Stock Messaging App Locks and is Slow
I upgraded to a Samsung Galaxy S4 (from iPhone) and still trying to make the transition and learn all of the new features.
One issue I have is with the stock messaging app. It completely freezes up at times. I cannot back out of a conversation thread. Messages do not go out. Eventually I will receive a message saying this app has frozen do I want to wait or close. Finally the messaging app doesn't load at all and I have to reboot the phone to get the app back.
What can I do to solve this problem and have the messaging app functioning smoothly and properly?
Notes:

I am running 4.2.2.
Memory is 8+ GB available
Only a few apps are running (I know how to close open apps)

Do you notice if the issues might occur at times where you're not getting good Cell/Data coverage? Just a hunch but the freezes and hold-ups might be due to lack of signal to communicate back and forth...The app shouldn't be responding like it is though, but there you have it.
You might want to try finding an alternate messaging app in the Play store to see if you get better performance/reliability.

You can install third party messaging apps from play store.

@Namuna - Coverage seems okay. Do you have any messaging apps to recommend? I am new to Android.

Go SMS Pro is pretty popular

If you are coming from an iPhone and looking for a better messaging app, check out Go SMS Pro and use an iPhone theme.
This app allows you to customize several things while still looking very similar to the iPhone's messaging interface. I always install Go SMS over the default messaging app and you might just want to give it a try, especially since you are coming from iOS. There are other plugins that are all free that allow you to view iOS emojis and other cools things like that.
Let me know if you still have the same issues with this app as well.
btw, congrats on smartly making the switch ;)


text:
Do I root to my model, or my version number?
When I rooted my last phone, I was able to find a detailed tutorial made specifically for the model I had. It was great, because I knew I had fully compatible tools and ROMs, which limited my amount of fumbling around.
I don't see anything out there for my new (to me) phone. I've seen generic guides for my Android version, but since it's specific to my carrier, I am wondering if I can just jump right in and start trying it out.

Can you specify what is the make and model of your "new" phone?

I'm currently using a Samsung Galaxy Attain, but if possible, I was hoping to find out if there was an answer that isn't phone-specific, or if it's case-by-case.

See also http://android.stackexchange.com/q/49925/16265

In order to root an Android phone, you have to take into account the Manufacturer of the phone and the Model, and also you need to take into account the Android Version installed. The process to root a phone is based on some exploit in the system, and each Android version with each model has a different method, which takes advantage of different exploits.
There are common exploits across some models, but in general, you need to look for a rooting method for your phone model and the Android Version it has.
I have used this page on some occasions to look for tutorials, but you can also look in xda developers


text:
how to arrange icons in TSF Shell?
I'm using TSF Shell, which allows you to drag your application icons around in an overlapping manner. But how do I tell TSF Shell to automatically arrange my icons neatly in rows using a grid?

You can use the 'lasso' option for that. It works real cool.


text:
How do I get the hidden achievement in the new Google Play Games app?
I've heard that there's a secret "easter egg" achievement in the new Google Play Games app, how can I get that achievement?

From the main listing of games in the Google Play Games app, you need to swipe the old Konami Code:
↑ Up, ↑ Up, ↓ Down, ↓ Down, ← Left, → Right, ← Left, → Right (and then when the retro button grid pops up), B, A, ▶ Start.

You should then see an achievement notification pop up.

Here's a YouTube video that demonstrates how to do this.
via Android Central


text:
How to turn off keyboard sound on Nexus 7 2nd gen
I already have touch sound turned off, but still hear keyboard sound.

I believe this will fix it:
Go to Settings, Language & input, Google or Android keyboard settings then untick the box next to "Sound on keypress".

Go to settings, sound and notification, other sounds, touch sounds.

Thanks for the answer, this answer may be valid in some cases, but in this one the question specifically says that "touch sounds" are already off.


text:
Booting into recovery from terminal
How can I boot into the recovery from terminal? I'm using LG p970/CM10/cwm5

Do you mean from the terminal on your desktop (using adb) or from a shell on the Android device itself?

Try reboot recovery, though it doesn't work on all devices. You might also need root for this, so first try su.

su root? Simply su should do :)

CM12 and perhaps CM11 too has ADB wireless option under Developer settings, and combined with "adb connect" you can boot into Recovery mode without needing su. But having CM already means you'll be having root access too, so how is this comment useful? -- Well for those running stock CyanogenOS. :) // But that's just command-line way, Developer options also has Advanced boot options, so GUI will provide "reboot to recovery" option as well. -- Warren T. Voider came up with this part.

It may not work if you have not-always-compatibile busybox reboot symlink in a PATH that is more privileged than /system/bin (or /system/bin toolbox symlink has been overwritten), it may lie in /sbin if using custom kernel with bb included for example. If so, try:
"toolbox reboot recovery" (jb)
"/system/bin/reboot recovery" (kk - however which one will work my be also dependent from the manufacturer...)

If you are running CM11 or CM12 you can simply go to Settings> About Phone> and tap Build Number 7-10 times to unlock Dev Options. Once unlocked you can go to Setting > Developer Options and select Advanced Reboot, this will add a "Reboot to Recovery" option to your reboot menu. Easiest method I have found to get unto recovery without installing a 3rd party app or using a terminal command if your phone doesn't want to accept a multi button sequence. Also note that in Cyanogenmod 12 you have to enable the Superuser root access in the Dev options first I believe.

OP plainly wrote: "I'm using LG p970/CM10/cwm5" -- CM10.

I added a comment mentioning you and the gist of your answer on the accepted answer, in case your answer is removed for some reason. :)

I'm afraid this doesn't answer the question for a quite different reason: OP asks how to do that from terminal – which your post does not cover at all.


text:
Why do my photos look fantastic on my HTC One X, but not that good on a PC?
The photos I take with my HTC One X look excellent on the phone screen, but when I copy them to a PC or laptop and view them on a larger screen, they don't look nearly as good.
Is HTC employing a filter or enhancement to make the photos look better? Could I do the same to the photos after copying them to my laptop?

What does "not nearly as good" mean? Colors? Sharpness? Brightness? "not nearly as good" is a bit vague to give a sound answer on.

Generally when you see an image on a bigger screen, you seems to notice blemishes quite apparently. The pixel density of the phone is greater than your monitor and hence could be this feel.

First, HTC is not ...employing a filter or enhancement to make the photos look better....
Second,
This is the color settings of the screens. If you transfer a photo taken from a Sony device camera to a Samsung mobile device, you will see a huge difference. That difference is that you can't see the vividness and cleanliness (i.e. the beauty ) you saw in the photo of the Samsung phone.
Explanation: The mobile phones has a PPI or DPI more than 300 whereas the computer monitors have around 150 - 200. Since you are seeing the pictures in a lesser pixel density while you are viewing them in your PC, you may fell that they don't look nearly as good.
If you want the beauty you saw in your phone, use Photoshop or any other photo editing app to increase the colors a little and adjust brightness and/or contrast or curves. Our fellow SE members of Photography Stack Exchange will be glad to help you.

I'm sorry guys! No offence to Samsung owners!! O:)


text:
Boot HTC Desire S into recovery mode without power button
Hi Android Enthusiasts,
The power button of my HTC Desire S is broken (no response whatsoever), so I have to connect my phone to a usb cable to get it out of stand-by mode. I understood that with a custom rom I can use a volume button for instance to get it out of stand-by mode. However, for flashing the rom onto the HTC Desire S I have to boot it into recovery mode. Which involves pressing the power button...
Any alternative ways to boot the phone into recovery mode?

Yes:

Make sure ADB is installed on your PC (see e.g. Is there a minimal installation of ADB?)
Make sure you have USB debugging enabled (Settings → Development)
Connect your device to the PC via USB
On the PC, open a command prompt and type adb reboot recovery

Your device should now reboot into recovery mode.

If your device is rooted then you can download an application called Quick Boot from the Google play store.
Check this https://play.google.com/store/apps/details?id=com.siriusapplications.quickboot
This app will let you quickly boot your device in various modes (including Recovery).
Thanks


text:
How to switch the GSM/3G module off?
I only use my smartphone (Samsung Galaxy Chat) as a "pocket computer" (with WiFi) and don't use it to make telephone calls (I use a dual-SIM "dumbphone" for this). All the time it shows a cellular network signal indicator and reports that it can make emergency calls. Can I switch it off to save battery?
Some years ago, when I had a Benefon Esc! GSM+GPS phone, I could independently turn its GSM and GPS modules on/off. I wonder if this is possible in modern day smartphones.

You can switch your phone to Airplane mode - this will shut down ALL radios. After this, turn on ONLY the WiFi and you'll be able to use it as a WiFi only device.

That's it (according to the indication) thanks.


text:
Which Android runs which Linux kernel?
Is there a list of which kernel version comes in each Android AOSP version?
Or lets say, which version /proc/version would spit out.

Related: Why are there so many different Android kernels, What is the difference between the Linux Kernel and the Android Kernel?

Linux version in AOSP

Android Version
API Level
Linux Version in AOSP
Header Version

    1.5   Cupcake
3
(2.6.27)

    1.6   Donut
4
(2.6.29)
2.6.18

    2.0/1 Eclair
5-7
(2.6.29)
2.6.18

    2.2.x Froyo
8
(2.6.32)
2.6.18

    2.3.x Gingerbread
9, 10
(2.6.35)
2.6.18

    3.x.x Honeycomb
11-13
(2.6.36)
2.6.18

    4.0.x Ice Cream San
14, 15
(3.0.1)
2.6.18

    4.1.x Jelly Bean
16
(3.0.31)
2.6.18

    4.2.x Jelly Bean
17
(3.4.0)
2.6.18

    4.3   Jelly Bean
18
(3.4.39)
2.6.18

    4.4   Kit Kat
19, 20
(3.10)
2.6.18

    5.x   Lollipop
21, 22
(3.16.1)
3.14.0

    6.0   Marshmallow
23
(3.18.10)
3.18.10

    7.0   Nougat
24
 3.18.48 4.4.0
4.4.1

    7.1   Nougat
25
 ?
4.4.1

    8.0   Oreo
26
 3.18.72 4.4.83  4.9.44
4.10.0

    8.1   Oreo
27
 3.18.70 4.4.88  4.9.56
4.10.0

    9.0   Pie
28
         4.4.146 4.9.118 4.14.61
4.15.0

   10.0   Q
29
                 4.9.191 4.14.142 4.19.71
5.0.3

Table compiled from:

Wikipedia Android version history (in parentheses; can't find its source)
android / kernel / common / Makefile (the Linux in AOSP)
android / platform / external / kernel-headers / original / uapi / linux / version.h (the Linux headers as used by Bionic in AOSP)

Note: other “distributions” of Android might run different kernel versions.
Anyone is welcome to correct and expand this table. Please keep formatting.
Why Android OS/kernel version mismatches
OEMs tend to ship their major Android updates with a similar kernel to the one the device was initially released with. This is most likely to avoid hardware and driver incompatibility issues with a newer kernel. For example, a device that has been updated to run Android 8.0 Oreo but originally shipped with 6.0 Marshmallow may still be running Linux 3.18.x instead of Linux 4.10.x.
Vendor Test Suite (VTS) requirements on Linux version
According to a 2017 article on XDA-Developers (shortened):

One aspect that has been up to the OEM is the Linux kernel version but this is changing with Android Oreo.
As long as the OEM was able to pass the certification tests that Google lays out, then they didn’t care what kernel version was used in a new device. This generally wasn’t an issue as most OEMs would use the same version of the kernel for that generation that other OEMs were using, as it is tied heavily to what the hardware drivers support. However, some had been falling through the cracks and this started to cause security issues. This is something that Google has been taking seriously lately so it makes sense that they would want to start mandating this.
Starting this year with smartphones which ship with Android Oreo, Google is requiring that all SoCs productized in 2017 must launch with kernel 4.4 or newer.
Currently existing devices that are upgraded to Android Oreo are only required to run kernel version 3.18 or newer, and will not have to be upgraded to support Project Treble.

According to https://android.googlesource.com/platform/test/vts-testcase/kernel/, there was a requirement on the Linux version, VtsKernelConfigTest or VtsKernelVersionTest, on 8.0, 8.1, and 9.0, but later removed on 10.0. For 8.0 and 8.1, it requires the version to be either 3.18, 4.4, or 4.9. For 9.0, it requires the version to be at least 4.4.107, 4.9.84, or 4.14.42.
More technical and recent information available directly from the AOSP website: https://source.android.com/devices/architecture/kernel/core-kernel-reqs

There's no hard fast rules involved! For instance, ICS/JB on Zte Blade used kernel 2.6.35, ICS on Sony Xperia Mini was 2.6.32... take this with a pinch of salt as its only a guideline :)

I can completely see why different devices running the same Android version would run different kernels, but this table is just a rule of thumb and yes I would like a grain of salt with my rule of thumb =)

Let’s restrict the table here to AOSP Android!

But Android Marshmallow 6.0.1 based MIUI 8.2 using Custom Kernel, Version : 3.18.24
And Kernel Vers

Note that even Google isn't following this. Just checked the emulator with API 26 and the kernel is 3.18.56+

My Sony Xperia Z5 Premium runs Android 7.1.1 with kernel 3.10.84 yet the XA1 runs 7.0 with kernel 4.4.15. Likely due to kernel-mode drivers.

I installed 6.0.1 on a Nexus5 and the about page claims I have kernel version 3.4.0. Any chance there's a bug in the about page?


text:
Would Samsung Galaxy Note II battery work on Samsung Galaxy Note?
Would Samsung Galaxy Note II battery work on Samsung Galaxy Note?
Would it fit and would the 3100mAh be a problem because the original of the Note is only 2500mAh?

It won't fit, The Note 2 batteries are physically larger than the Note 1's battery slots. Your best bet is finding a good third-party extended battery.


text:
What is `Snapshot` and `Use host GPU` emulation option(s) for?
When creating an emulator device, the option Emulation Options makes me confused. What do Snapshot and Use host GPU mean?

The Snapshot option speeds up the boot of the emulator by saving a snapshot of its RAM once it has booted, and restoring from that snapshot on future uses. That way, it doesn't have to run the boot process (which is slow, because it's emulated) every time you start the emulator.
The Use Host GPU option uses the host computer's OpenGL implementation (which is probably hardware-accelerated, on your real GPU) to evaluate OpenGL commands inside the emulated system. Put another way, when a program inside the emulator uses OpenGL for graphics operations, the work goes out to your real GPU, and the result goes back into the emulator, instead of emulating a GPU (which is very slow). The result is a significant speed-up, especially when you consider that most view and canvas drawing uses OpenGL in Android ≥ 4, even in non-graphics apps.
You can't have both options turned on at once.

Which option would speed up testing a PhoneGap app (primarily consisting of Angular+Bootstrap) the most?

This depends on whether you want a faster boot or better runtime performance for the emulator. Snapshots allow you to boot almost instantly but Host GPU speeds up the emulation itself.

@Micah-psIloveyou If you have a follow-up question, the best way to get good answers is to post it as a new question. Nobody will see it buried in the comments.

@onik, Why couldn't both be combined?

The Snapshot option allows you to use a feature that's similar to the Hibernate function in Windows. It saves the contents of the emulator's memory to disk when you close the emulator, so that when you open it, it doesn't have to boot the OS, but instead it can load the memory contents from the disk and resume from where you left off. This allows you to start the emulator faster.
Use host GPU means that instead of using the CPU to render the graphics, it uses the computer's graphics card. This speeds up graphic-intensive processes. Details and requirements can be found on developer.android.com.
You should note that Snapshots and graphics acceleration are mutually exclusive, so you can't use both.

Which option would speed up testing a PhoneGap app (primarily consisting of Angular+Bootstrap) the most?

Usually in phonegap/cordova you keep the emulator running all the time and just re-deploy the apk to the emulator. I keep the GPU turned on. To speedup the startup time anyway I read that it is good to have a smaller sd-card image in use.

@onik, Why are they mutually exclusive?


text:
managing multiple contact sources as gmail contacts
I'm on a google nexus 4 (up to date, non-rooted) and I'm using gmail and google contacts for my contact/messaging needs. Additionally I'm pulling contacts from facebook, linkedIn, xing (German linkedIn clone) and google plus.
Is there an easy way to merge contact info from other networks into the gmail contact when joining/linking contacts from gmail and other networks like facebook and linkedIn?
I wouldn't mind using a third party app to do the footwork (joining, unduping, etc.) but I'd like to keep and update the data in my gmail contact list as I am using this list half of the time on my desktop. I don't mind using another contacts app for viewing/browsing and calling/texting my contacts but I don't want to depend on one forever and I don't want to redo everything again and again everytime I switch my phone and/or contacts app
I know that Smartr and Rapportive (Desktop only) can do a lot of association stuff but in  the end all the data that happens in Smartr stays in Smartr.
Things I'd like to have:

Data

Contact Name
Picture (assigned by me, default g+ with facebook or linkedIn as fallback)
Nickname
basic gmail stuff, multiple numbers, mails, addresses, birthday, other dates, urls
other network profiles as "profile URLs" or sound "other URLs"

Functionality

easy linking/joining and un-duping
data storage in gmail contacts as fas as possible
compatibility with other apps like smartr or rapportive

The usual answer on that was (at least a while ago) using the GMail web interface. But with all those re-desings lately, I'm not sure if that feature does still exist, or whether it was replaced by some colorful "tile"...

Thanks for the reply. I'm working primarily with the Gmail Web Interface since I'm a web dev and bound to my pc 9-5 + side projects. But everytime I start updating contacs I feel there are either fields or sometimes even entries missing...

Since their latest relaunch, I use those Google tools only when forced to. They're getting worse each day (at least that's my subjective feeling). But give me a few minutes, I just happened to remember an alternative solution which might work for you. Will place it as answer.

KADlancer - check out http://www.fullcontact.com. (Full disclosure: I work for them, so I'm a bit biased. But the issues you mentioned are exactly the issues we're trying to solve).
We currently have a web app in private beta that pulls in contacts from various Google Contacts/Gmail sources, as well as Facebook, Foursquare, LinkedIn, Twitter, etc. It then adds social profile data to each, normalizes & de-dupes them, and syncs them back in real-time.
Within the next month we plan to roll out our public beta, which will support the linking of all of the above sources - meaning you can unify contacts across all your social networks/Google accounts and have all your contacts in one place, automatically up-to-date. Because we offer two-way sync in real-time, changes made in Google Contacts sync to FullContact, and vice-versa - meaning that your data is your data, and stays where you want it (no walled gardens).
Again, I work for them, so you'd probably be right to take what I'm saying with a grain of salt. But based on what you posted, it looks like the FullContact Address Book will do almost everything you're looking to do (with the possible exception of Xing, which is currently not supported, but on the roadmap). I'm not aware of any other app out there that does quite what we do, save Smartr - which it sounds like you've already tried.
Good luck!

sounds amazing, any chance for me to get into the closed beta and give it a go? I'm willing to put hours of work into feedback mails / posts if your solution ends up exactly what I need for this special problem (which bugs me ever since getting my first smartphone).

Unfortunately, I don't control that - I know they're pushing hard to get one universally-requested major feature finished before letting in any more beta users outright. But if you sign up for the wait list, they should be able to get you in within the next month. (& I definitely understand the "bugging me ever since my first smartphone" bit. I've been having the same issue as far back as my Handspring Treo. Ridiculous.)

Already signed on directly after reading your reply. Waiting and looking for some tea right now (sorry, reference to a German proverb). Looking forward to give FullContact a go.

after finally getting access to fullcontact, I have to say its definitely headed in the right direction. I'll give it a go for a while and report back as soon as I can tell if this is realy what I was looking for. Looking good so far!

Awesome! It's definitely in (open) beta, so any and all feedback is very much appreciated. We want to build a product that you love.

As Google's web frontends get worse each day currently (there used to be a nice way to merge contact with GMail, but with the latest re-designs I'm not sure which features are still left in working order), you might wish to take a look at a few app-based solutions:

Contact Remover Plus: Other than the name might suggest, the Plus version also offers to merge contacts, copy contacts between accounts, and move contacts between accounts
Contrack mentions some "linking" stuff (but not much details)

The first one looks the most promising in your context. Not sure about Facebook etc. though, as I don't use those networks.

Thanks a lot for your suggestions. I just had a look at both. Contrack seems to go into another direction with a heavy focus on checkins and interactions. The first one (Contact Remover Plus) looks interesting but after reading the developer's description and warning about syncing merged contacts to external services that might result in data loss I guess I chicken out and continue my search.

I'll upvote you as soon as I have enough reputation as your links are helpfull even though they are not a perfect match for my problem.

As you have already more than 15 rep, feel free :) Glad I could help!