text:
Why do I need to remove my battery periodically to fix phone problems?
On my HTC MyTouch 4G (Android 2.3.4), twice now the diagnosis for odd failures was to take the battery out, wait a minute, and replace it.  (The first failure was loss of network; the second was web sites only partially working, e.g. I could read SE sites but not log in.)  Both times popping the battery fixed it, and my provider told me I should do this every couple months as "preventative maintenance".  This violates my mental model.  So, clearly, either my mental model is wrong or HTC and the folks at T-Mobile are having fun with me.  I'm going to start by assuming it's the former.
I power the phone down at least once a week.  I think of this as being like rebooting a laptop computer; when it's powered down I don't expect the battery to be retaining any state.  But if that's true, why does performance degrade over time?  What is my phone doing with its battery during these times?  Does periodically powering down do anything useful, like kill long-running processes?
I tried Google and reviwed the "battery" questions here before asking.

Sounds like a design flaw to me. You shouldn't have to remove the battery except to...change the battery.

It's not the battery retaining state, it's the phone circuitry retaining state. Even when you use a "power off" command and your phone looks powered off some of the circuits will still be connected to the battery so that the phone can be turned on by just pressing the button. So there will be some circuitry powered on even after the phone was "powered off".
This is likely a bug in the circuitry. This actually happens to devices - you sometimes need to "power cycle" them by unplugging them from the power source and then plugging them back. In case of a mobile phone that requires removing and then installing the battery.

I had no idea that the circuits could retain state when powered off.  Thank you.  ("Bug in the circuitry" explains why people with other phones don't seem to have this problem.)

@Monica Cellio: Actually the phone been "powered off" using the "shut down" command doesn't mean that the device is powered off - some of the circuitry will still be connected to the battery, otherwise how would it turn on when you press the button?


text:
How does this dialer work?
When I press certain numbers on the dialer of my phone, names are brought up which don't make any sense. I've used T9 dialer, but I can't understand this. For example le, typing 77 brings up names starting with Ap, and Dr. Typing 34 brings up names starting with He, and Ad. I just wanted to know if there's any reason for this.
The OS is Jelly Bean 4.1.1
EDIT: As some of the answers point out that it may be a part of a number of one of the contacts. I've checked it before, it only happens after I type three numbers. And if it is a part of a number, that string is highlighted.
But when I type just two numbers, the names come up with their first two letters highlighted.

Isn't it possible those are just number sequences found in the telephone number of the listed people? The list refines as the numbers are input.

The dialer will look for things that match the T9 query as well as search your contacts that have the string of numbers associated with their phone number.
For example if you have contact John Smith with phone number 123-456-7890 and you dialed "78" he would show up because that string matches part of his phone number. If you dialed dialed "56" he would also show up because that matches his name "Jo" as well as part of his phone number "56".
I hope that helps!

source: Stack Exchange

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

sort: votes


text:
Clear the "Do not ask again" dialog in Gallery when changing Wallpapers
As you might know, when you try to change the wallpaper on ICS (for your homescreen), the OS will ask if you want to set the same wallpaper to the lock screen, and the proper "do not ask again checkbox". By mistake, I pressed it, but I want it back now
Any way to achieve that?
BTW, I checked the "Clear Defaults" in the Gallery app - nothing. Using Android ICS 4.0.3

I don't get that option in my vanilla ICS. Which phone do you have?

I have a Samsung Galaxy S2 I9100. But I found out the problem — read below!

The problem was a silly one. When you try to select a wallpaper you're given two choices: full wallpaper for the virtual desktop (option 1, scrollable wallpapers) and a fixed wallpaper (the second option).
If you select the second option, it will ask if you want to use the same wallpaper for the lock screen.
However, if you select the first one, it won't ask you anything (because it can't be set) — ths was the root of the problem.
I'm assuming that, if you do tap the "Do not show this dialog again" can be reset by tapping "Clear defaults" in the Gallery App.

Gallery>clear cache and clear data> uncheck and recheck notifications.

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


text:
Cannot make changes to specific folder
My phone is rooted with aokp build 38 on it. It is a Verizon Galaxy Nexus (toro)
There is a folder /sdcard/data that I can't make any changes to. Some of my apps are trying to use this folder but are not able to because any changes to this folder fail.
I tried deleting it but was unable to. I even used adb shell with root access and tried to rmdir, but it says "Permission Denied"
I also tried to chmod 777 to give full access to the folder, but I still was unable to make any changes to it.
I'm at a loss as of what to do to make this directory writeable again.

Make a backup of your data first.

every folder and file in the /sdcard/data directory is 0 bytes.

This looks like a corrupted filesystem or a defective sdcard (see correction). Especially, folders have a usual minimum size of 4.0K.
I'd suggest you to back up your data first, then check for errors:
Does "dmesg" show filesystem errors on mmcblk0 or similar?
If so try to backup, reformat sdcard (see correction) and restore or replace the faulty sdcard.
(EDIT) Correction:
The Galaxy Nexus has no SDCard but a unified EXT4 filesystem for /data that also includes /sdcard (which is symlinked to /data/media). You might solve the problem with a wipe. But that will also delete all of your /sdcard content too.
You might have luck entering recovery and adb'ing into it to fsck.ext4 your /data partition, I'm however not sure if your rom supports this command

 # boot to recovery first!
adb shell
cat /proc/partitions
 # look for the biggest one and replace the ?? accordingly
fsck.ext4 /dev/block/mmcblk???

Here's an external report about a similar issue:
http://forum.xda-developers.com/showthread.php?t=1541379

How do I get adb to recognize my device when it's in recovery?  It always says device not found.  (I feel like it should just see it, but maybe I'm wrong.)

Some recoveries don't start adb internally but offer an option to do so in the menu. If adb is missing altogether you can start a different recovery temporarily: download a recovery image from https://clockworkmod.com/rommanager and boot to fastboot mode. Then execute 'fastboot boot <recovery-...img>' Adb should work until the next reboot then

I ended up just restoring to stock.  I'll reflash a custom ROM later.  I couldn't get my computer to recognize the phone when I was in recovery.  I believe your answer was correct though so I'll mark it as such.

Try going to /data/media, it should be the same folder as /sdcard. I think the files you're trying to delete might be virtual, I had this exact problem while trying to clean up in /sdcard/Android/data until I realized that I could also find them at the path specified.

what are 'virtual' files on a vfat/ext4 partition? the 0-byte sizes of folders are a rather clear indication of fs problems, most probably some directory inode is not accessible/parseable and gets stuck at 0 byte.#


text:
Is this a virus?
When I try and open the "Movies" application on my phone (HTC Vivid w/ Sense 3.6 and ICS), I'm given with this notification (see image):

Screenshot (click image to enlarge)
Now I don't think this is legit, so what do you think? Is this a virus? And if it is (which i think it is), how can I go about removing it?

OP: I think you're jumping to wrong conclusions. Where did you download that from? If its not from Google Play, you will get that message as I've explained in my answer below!

OEM manufacturers tend to bundle apps with new handsets that are sitting there until you install them :)

Rest assured, that is not a virus, its a warning dialog to make you aware that you may have the app install from outside of Google Play blocked. It is normal! :)
To proceed to check and confirm it is indeed unblocked...
Go into Settings > Security > Device Administration, tap on "Unknown sources", a dialog box appears, tap ok as that's a standard disclaimer, which is normal de-facto thing.
For GB, Menu > Settings > Applications, check "Unknown Sources" and again, similar dialog appears as a disclaimer.
Tap Ok to continue and back out of it.

More likely that the movie App just wants to get installed. It's not uncommon that 3rd party software is installed this way.

The thing that worried me was that it was installed by default my the OEM, but if you say its ok, then I'll give it permissions


text:
Can I have a "force close a specific app" shortcut on my screen?
My Google Chrome frequently hangs for no apparent reason. Application is active (responding), but tabs are blank and nothing loads... The only solution that I found is to go into Settings -> Apps -> Google Chrome and "force close" it. Then I re-open it, and it works OK again, for some time.
I'd like to automate this manual "force close" process, e.g. I'd like to have a shortcut on my screen that terminates Chrome for me. Any other easy way to close Chrome is acceptable too.
My device is Asus Transformer, rooted.

You can get halfway there by adding a shortcut to apps settings.

Maybe try Dolphin Browser, it might fare better than Chrome (bear in mind Chrome is still early stages...)

I've ended up using Tasker, it is trivial to create a task to kill a specific application (Google Chrome), than add a shortcut (widget) to that task on the screen.
Edit: I've actually created a task that not only kills Chrome, but restarts it afterwards as well, all in one click:

Very neat and handy app, powerful as well :) Good for you, I saw that on twitter, that there's going to be a new Tasker that will enable you to save them as "mini independant programs" outside of Tasker..

Another option that works well is Automate, although this requires root.

I implement such a Tasker 'Kill App' task for Whatsapp - when I want to pause it. But it does not truly "Force Close" it. That is, Whatsapp remains active, receiving messages. Is there a solution that really "Force Closes" an app, incl. its background process running?

Get a process killing app from the market like 'Advanced Task Killer', it will allow you select which processes you would like to kill and then do so by clicking a single "kill" button.
Warning!! Of course forcibly "killing" a process is not recommended as it can break your application (think of what would happen if a process is writing to file and then is suddenly terminated, you could end up with a corrupt asset!!!) or even, in worse conditions, harm your system.
you will either have to wait for it to close by itself or just use a different browser. so the answer is yes, but don't do this.

Using task Killer is frowned upon, Android != Windows, where you can zap at a process to kill it a lá Windows Task Manager. You could actually end up de-stabilizing Android and... also, drain the battery, in the context of services, kill 'em, they'll end up restarting - juice sucked! which is the very nature of services. Let Android do its job

Hence -1 from me for recommending it. The answer is don't...use...any...task...killers...what...so...ever!

actually killing a process (pid) is a linux native method of forcibly closing a process, of course you would use it only in extreme conditions. I guess an edit is in place!

Android is not Linux! :) Don't even think it is, just because it has a limited busybox userland tools to mimick a full blown Linux desktop/server....

just trying to show the similarities. btw, edited my post, thanks guys!

@t0mm13b: Although this is not something that I would like to do (still a multi-step process), this one specific case is probably ok task for a task killer. After all, all I want to do is kill a misbehaving task quickly and effortlessly (on demand - not automatically).

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


text:
Android customization Galaxy Note
Recently, Android ICS has been released in my country (Hungary) also for the Samsung Galaxy Note. That's cool, the phone updated itself to Android 4.0.3 and at first sight it was really cool and fast. But...
To be honest, the Wi-Fi disconnects and the battery gets empty in half of a day... These 2 make me really angry and I was thinking about rooting, which I have successfully done today, but it still didn't help at all on my problems. Okay, the UI might be a little faster...
So. I thought I might have to change the ROM to a custom one.
Now I have more questions about this:

I wish to modify my phone on a way I can easily turn it back to the factory state (no wonder, warranty). How to do this/is it possible?
Is it possible to "put up" more ROMs and when I'm turning on the phone just select the one I want to use (just like you'd install more OSs on a desktop computer)?
I would also want to know what are my options for a custom ROM for a Galaxy Note WITHOUT losing my S-Pen functionality, so which ROMs should I count in?
How to freakin' achieve these above questions if everything is ok? =D

Thanks in advance! =)
(Links and experiences are welcome also...)

Only devices with NVIDIA Tegra chips in them can be completely restored to factory conditions.
When you root your phone, the warranty is void, and there is no sending it back.
You can Back-Up a ROM and before booting, wipe the phone's ROM and restore one of the backed up ROMs.
Backing up and restoring is very time consuming, though.
You would only want to do that so you could perhaps have an AOSP ROM, a TouchWhiz ROM, and perhaps a CM9 or AOKP ROM as well--
Trust me, you'll be too busy flashing new updates to worry about switching between backups.
Head over to http://forum.xda-developers.com/forumdisplay.php?f=1346 for the low down on the rest. You can never read enough, really--
The different ROMs will be under the Development section.

Actually, I am backing up the phone now. I see now what you mean under time consuming... =D Anyway, Samsung can go to hell, I can't believe they have screwed up Android ICS so much... So if warranty goes for a freakin' awesome smartphone, so be it...

Oh! Well, I've never handled a Huawei-- But no- there are not many that I've come across.
HTC, Samsung-- cannot be reverted.
LG, some Motorola's-- can be restored to factory condition-- but they all have NVIDIAs in them-
And what do you mean, benqus?
I don't own a Samsung, myself, but they're top of the line! I would rather have a GSII than the HTC XE
Is TouchWhiz that bad? -- I mean, it's gotta be better than what HTC did with Sense--
-- I highly recommend Apex Launcher ontop of either CM9 or AOKP for the best  ICS experience--


text:
ADB does not reboot my Samsung Galaxy SIII I9300 to bootloader (download) mode
My device is Samsung Galaxy S3 I9300 and I did a complete factory reset. The device is NOT rooted yet. It works properly. I can do all of the following with my device:

Power off using device keys.
Start in recovery mode and download mode using device keys.
device is detected properly in normal mode and recovery mode by adb when is connected to PC through a USB cable
I am able to reboot the device using adb reboot command
adb reboot recovery works well.

The problem is that if I run adb reboot bootloader or adb reboot-bootloader commands, the device is booted in normal mode, NOT in download mode. The only way to reboot the device in download mode is to use the Power + Volume Down + Home keys

There is another problem with this device that my help to solve this problem. For more information please see this question: (http://android.stackexchange.com/questions/97115/samsung-galaxy-s3-i9300-is-not-detected-by-fastboot-under-ubuntu-14-04)

From my experience with Samsung devices this is not a bug but rather a feature. The "download" AKA "ODIN" mode on Samsung devices is a proprietary alternative to bootloader/fastboot mode and I don't remember being able to boot to this mode in other than the hardware way.

The command below works for my s3.
adb reboot download

Could you provide the output of adb help? download option is not supported with reboot. See source code here: https://android.googlesource.com/platform/system/adb/+/refs/heads/master/commandline.cpp#192

As far as I know, adb reboot is shorthand that does the same thing as /system/bin/reboot binary, whose syntax is usage: reboot [-p] [rebootcommand]. From testing, reboot commands for Samsung-based devices are recovery and download. Samsung devices have a proprietary implementation of fastboot/bootloader mode called download mode, hence download option.

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


text:
Unable to find Android WebView in Google Play store
A recent Chromium blog post contains a screenshot of a Google Play store page for the "Android System WebView".

I am unable to find this page. I have tried searching the Play Store on my Nexus 7 2013 device (which has Lollipop on it). Interestingly, this page does not seem to exist on the web at all:

It seems so.. I checked the package name of the APK, and it should be com.google.android.webview, so the Play Store link should be https://play.google.com/store/apps/details?id=com.google.android.webview, but it doesn't exist currently.

@AndrewT. And I don’t even have it installed as an app. If I understand correctly, the WebView should exist as a separate app on Lollipop. I don’t see it on my Nexus 7 2013.

It isn't listed on the launcher. Try checking on Settings > Apps > All > Android System WebView. Meanwhile, after reading the blog post, I'm thinking that the Play Store is only available for beta tester first. So, for public users, you won't see it live.

@AndrewT. Ah yes, I see it. I got version 37 (the newly announced beta is version 40).

@AndrewT. Confirmed on the web (but apparently with restricted access) https://twitter.com/passcod/status/567177405182140416

Update
Android System WebView's update is now released for public. Still, if you want to get (beta) update earlier, then continue reading:

As the article says,

If you're making use of the WebView in your app, becoming a beta channel tester will give you an early start with new APIs as well as the chance to test your app before the WebView rolls out to your users.
The first version offered in the beta channel will be based on Chrome 40 and you can find a full list of changes on the chromium blog entry.
To become a beta tester, join the community which will enable you to sign up for the Beta program; you'll then be able to install the beta version of the WebView via the Play Store. If you find any bugs, please file them on the Chromium issue tracker.

(Emphasis mine)
As of current, the WebView is based on Chrome 37, while the beta channel offers Chrome 40. Also, currently there is no update publicly available, hence the Play Store link displaying "Not Found". To be able to see page (and update the WebView), you have to join beta channel testing. The guide as provided on the Google+ community:

Join WebView Beta Channel community on Google+.
Sign up as a tester via this link.
Go to the Play Store page and ensure your devices are updated with the latest version.


text:
Google Voice SMS not showing notifications in Hangouts?
I have my Google Voice account setup through the Hangouts app for Android, on my un-rooted Galaxy S5 (with the Lollipop OTA).
When I have the application open on my device, and I receive an SMS to my GV number, it appears on screen.
If I don't have the application open, the phone still receives the message, but it does not give me a notification. I know background data is turned on, and it has received the message, because I can turn on airplane mode, then open the app, and see the message is there unread.
SMS messages sent to my carrier number as well as Actual Hangouts messages notify correctly whether the app is open on-screen or not.
Has anyone ever seen this before?

Are you sure you didn't disable the "Show notifications" option for Hangouts?  Settings -> Apps -> Hangouts, right under Force Stop.

Yes, I am sure. As I mentioned above, I still receive notifications for Hangout messages, as well as SMS messages, just not Google Voice SMS messages.

Just ruling out the low-hanging fruit first.  Next on that list - in Hangouts app, in Settings -> [your Google account], under "Google Voice - [your GV number]" section make sure a setting "Messages (Show SMS & voicemail in Hangouts)" is selected.

Yes, that setting is selected.

Do you have the actual Google Voice app installed?  I remember reading some article a while ago saying that it's still needed.

Then in the GV app's settings under "Sync and notifications", make sure the setting to receive text notifications is enabled.  It may be grayed out since your main SMS app is Hangouts, but it should still be checked.

Also, can you see if you are experiencing this issue? Basically every new conversation will have notifications disabled by default until you explicitly turn it on manually, and there is currently no way to override this behavior.

It looks like there is an issue with Hangouts app that causes notifications for new conversations with a given contact to be disabled by default, with no way to override this setting.  On the Conversations tab, these are denoted by a bell with a strike-through:

(click for larger image)
Once you open such a conversation you will see a message in red saying "Notifications off - You won't be notified of new messages" with an option to enable them:

(click for larger image)
Existing conversations for which you've enabled this setting will receive notifications normally.  If you delete the conversation, the setting will revert to "off".  Archiving the conversation keeps it enabled.
The details that are described in this thread (I suggest starring it to show Google that there is interest in this issue) match exactly what you are experiencing.  It has been brought up before, and was escalated to the Hangouts development team, who are already aware of the issue.  We can only guess when (or if) Google will fix this.

Well, in my instance, this looks like it is absolutely the issue that I'm having. I was able to reproduce the exact behavior you've described. What a frustrating bug. Thanks for finding this.

I found this post on a google product forum and it worked for me. After you follow the steps, if it helps, I used the following service to send a test text message to my phone knowing it wouldn't be in my contacts and IT WORKED :)
https://www.clickatell.com/test-sms-gateway/
Tokiyo said:
Found a solution trying to fix this problem. This will give you notifications of new messages from new numbers or new people on the Hangouts app.

Go to your Hangouts app
Menu
Settings
Your account email
Customize invites
Everyone Else
Select "Can contact you directly"

Source: http://www.reddit.com/r/Android/comments/2vjtje/try_this_fix_if_your_hangouts_app_doesnt_notify/


text:
Problem with updating from cm-12-20150228-NIGHTLY-taoshan
I've installed the cm-12-20150228-NIGHTLY-taoshan to my C2105 and now I want to update to cm-12-20150303-NIGHTLY-taoshan but I get this error.
This package is for device: C2105, C2104, c2105, c2104, taoshan this device is .

What can I do to solve this problem?
Same problem is with the cm-12-20150301-NIGHTLY-taoshan and also with downgrading to the cm-11-20140827-NIGHTLY-taoshan (which I had previously installed). It seems to me that the information about my device is missing. How can I add the information that this device is C2105/taoshan?
I've tried to get some information from my /system/build.prop file but it looks like the C2105 identifier is OK. Is it possible to turn off the device validation during new CM installation? This is what my current /system/build.prop looks like:
# begin build properties
# autogenerated by buildinfo.sh
ro.build.id=LRX22G
ro.build.display.id=cm_taoshan-userdebug 5.0.2 LRX22G a166b92e84 test-keys
ro.build.version.incremental=a166b92e84
ro.build.version.sdk=21
ro.build.version.codename=REL
ro.build.version.all_codenames=REL
ro.build.version.release=5.0.2
ro.build.date=Sat Feb 28 10:03:21 PST 2015
ro.build.date.utc=1425146601
ro.build.type=userdebug
ro.build.user=jenkins
ro.build.host=cyanogenmod
ro.build.tags=test-keys
ro.product.brand=Sony
ro.product.name=C2105
ro.product.board=qcom
# ro.product.cpu.abi and ro.product.cpu.abi2 are obsolete,
# use ro.product.cpu.abilist instead.
ro.product.cpu.abi=armeabi-v7a
ro.product.cpu.abi2=armeabi
ro.product.cpu.abilist=armeabi-v7a,armeabi
ro.product.cpu.abilist32=armeabi-v7a,armeabi
ro.product.cpu.abilist64=
ro.product.manufacturer=Sony
ro.product.locale.language=en
ro.product.locale.region=US
ro.wifi.channels=
ro.board.platform=msm8960
ro.build.characteristics=phone
ro.cm.device=taoshan
# end build properties
#
# from device/sony/taoshan/system.prop
#
#
# system prop for taoshan
#

ro.sf.lcd_density=240

#
# ADDITIONAL_BUILD_PROPERTIES
#
keyguard.no_require_sim=true
ro.com.android.dateformat=MM-dd-yyyy
ro.carrier=unknown
com.qc.hardware=true
ro.vendor.extension_library=/vendor/lib/libqc-opt.so
ro.telephony.ril_class=SonyRIL
wifi.interface=wlan0
wifi.supplicant_scan_interval=15
persist.hwc.mdpcomp.enable=true
wlan.driver.ath=0
dalvik.vm.heapstartsize=8m
dalvik.vm.heapgrowthlimit=96m
dalvik.vm.heapsize=256m
dalvik.vm.heaptargetutilization=0.75
dalvik.vm.heapminfree=2m
dalvik.vm.heapmaxfree=8m
ro.opengles.version=196608
ro.ril.transmitpower=true
persist.radio.apm_sim_not_pwdn=1
DEVICE_PROVISIONED=1
rild.libpath=/system/lib/libril-qc-qmi-1.so
ril.subscription.types=NV,RUIM
telephony.lteOnCdmaDevice=0
ro.use_data_netmgrd=true
ro.telephony.call_ring.multiple=false
ro.ril.telephony.mqanelements=6
ro.qualcomm.cabl=0
ro.cwm.enable_key_repeat=true
persist.debug.wfd.enable=1
persist.sys.wfd.virtual=0
ro.qualcomm.bt.hci_transport=smd
persist.timed.enable=true
qcom.audio.init=complete
persist.audio.fluence.mode=endfire
persist.audio.vr.enable=false
persist.audio.handset.mic=digital
persist.audio.lowlatency.rec=false
media.aac_51_output_enabled=true
ro.qc.sdk.audio.ssr=false
ro.qc.sdk.audio.fluencetype=none
lpa.decode=true
persist.gps.qmienabled=true
ro.gps.agps_provider=1
ro.error.receiver.system.apps=org.cyanogenmod.bugreport
ro.rommanager.developerid=cyanogenmodnightly
ro.com.google.clientidbase=android-sonyericsson
ro.url.legal=http://www.google.com/intl/%s/mobile/android/basic/phone-legal.html
ro.url.legal.android_privacy=http://www.google.com/intl/%s/mobile/android/basic/privacy.html
ro.com.android.wifi-watchlist=GoogleGuest
ro.setupwizard.enterprise_mode=1
ro.com.android.dataroaming=false
ro.build.selinux=1
persist.sys.dun.override=0
persist.sys.root_access=0
ro.cm.version=12-20150228-NIGHTLY-taoshan
ro.cm.releasetype=NIGHTLY
ro.modversion=12-20150228-NIGHTLY-taoshan
ro.cmlegal.url=https://www.cyanogenmod.org/docs/privacy
persist.sys.recovery_update=false
ro.cm.display.version=12-20150228-NIGHTLY-taoshan
ro.config.notification_sound=Argon.ogg
ro.config.alarm_alert=Hassium.ogg
ro.config.ringtone=Orion.ogg
persist.sys.dalvik.vm.lib.2=libart.so
dalvik.vm.isa.arm.features=div
dalvik.vm.lockprof.threshold=500
net.bt.name=Android
dalvik.vm.stack-trace-file=/data/anr/traces.txt

EDIT so I checked the "updater-script" file and it seems that the CM installer is trying to validate the property ro.product.device which is missing in my build.prop. So I've added it to the build.prop file and tried to install the CM again but... Still the same error!
I also tried to modify the build.prop and remove the validation but now I get error that the package is not valid because of checksum or something like that (I don't remember exactly)

I faced the same problem, exact same error message and was going crazy. :P
The problem in my case was that the recovery was corrupted. I just downloaded the recovery from here and update successful.
Hope this helps :)

You are already very close. If you are sure that the download isn't corrupt and you are sure that the file downloaded is indeed for your device, you can open the zip file, go to the updater-script and remove the part of the script where it validates which phone you have.
After this edit, the update should work fine.
Also, I'd mention it to the maintainer of the ROM, as multiple people may be experiencing the same issue.

Thanks for answer. The problem with this is that the checksum can't ve validated after I edit the updater-script. Do you have any idea how to solve the checksum problem?

Honestly, I would always just install it and test it for a few minutes, if nothing weird happens it's probavly all good. I always had a backup ready so I coould go back if neccesary and I've personally never bothered using checksums myself...


text:
Android not responding, screen off and battery drop
I have a Lenovo s890 that sometimes stop responding and back after about 1 minute. I have checked the screen and seem there is no problem with the screen. On the other hand when the cell phone stops working, then the battery indicator drops significantly that is really annoying. Do you have any solution for that?
Here you can a similar video that shows the problem.
https://www.youtube.com/watch?v=FB_w4WvDiUY

I guess you're unaware of the distinction between a forum and a Q/A site.  Consider taking a tour and a glance at [help]. Look especially about self-answer.

Hi @Firelord. Thanks so much I know the difference but finding solution in forums is so difficult at least for me but in SE  it is much much easier. It is the main reason I decided to post the solution here. Thenks.

No issues in posting a solution but as per the rules, a question field should only have a question. You can always answer your question in the answer tab. Please [edit].

See  this question as an example of self-answering. I had the same reason for doing it.

I played more than 3 months with the mobile phone and this is how to solve the problem. I Guess this solusion works for other mobile phones.
If you have a lenovo s890 (or other cellphones with similar symptoms) that sometimes stops and not responding or if your battery drains suddenly or if the screen goes off and does not back, then the problem is not with battery or screen. I have seen some people that asks for help and there are loads of solution that none of them work. The solution is a problem in the kernel of OS that manages CPU of the cell phone.
First install a CPU manager app from google play for example (link). Then
Decrease the maximum CPU frequency to one level down and set the governor to Ondemand (like screenshot).
I have tried other setting that none of them worked for me.


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Stop SD card from constantly unmounting due to underpowered
I had problems with constant unmounting of my SD card from phone when it was not on charger. The problem was with powering off some power when disabling display to save energy, but this power was needed to keep SD card mounted.
My phone is LG Optimus L1 II E410, but from what I found during my long search for solution, it is not the only phone affected.
How can I stop this from happening?

So what's your actual question?

How to prevent SD card from unmounting? LOL. Maybe you didn't notice I made it QandA style question, just because I lost like 5 hours to find the solution and thought it would be helpful to have it in some place where people would look for it.

So why is that wakelock app needed at all? What's causing the unmount to happen? I never encountered that on any device. Did you apply some "freaky" power-saving stuff?

What is this bit "problem was with powering off some power when disabling display to save energy"? Have you set it to disable other components when the screen turns off, or is this just something that you've spotted happening?

It is original, not rooted system with no special settings, so this is just something that I found out that was the problem.

The solution is to install program Wake Lock and set the setting to PARTIAL_WAKE_LOCK. This keep necessary power for SD card even if of charger and with disabled display. It obviously cause a bit more battery consumption, but far less then constant SD card remounting. No root needed.

I had the same problem on Alcatel POP C5 with Kingston 8GB micro SD class-10 card. First, I thought that the problem was with the phone. After replacing with another, borrowed card, the phone was working normal again, so I concluded that it was the bad SD card.
Using Wake Lock - PowerManager with PARTIAL_WAKE_LOCK enabled did solve the problem, partialy. I wanted the permanent solution so I keep trying to solve the problem.
The first time I realized the card was unmounting, when phone was on standby, was this summer when outside temperatures exceeded 35°C. I thought if hot temperature caused the problem, it might be also the solution to it.
First, I took my soldering iron and heat all MicroSD card metal contacts for approximately 10 seconds. After that, the phone was not unmounting the card for 20-30 minutes, but then it started showing error messages again. Then, I heated each contact, once more, for 2 minutes. The card was too hot to touch it with my hand, and I was worried not to melt the plastic. After that intervention, the card did not melt, all of the data was still on it and the card is working in my phone for 2 days now, without unmounting.
I hope that this is a permanent solution and that will help someone else too.
Just to say that I am not responsible if someone damage their card or data attempting to do this. DO IT AT YOUR OWN RISK!


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How can I view SMTP headers in the Gmail app?
I'd like to view the full SMTP headers of a message in the Gmail app, but I haven't found a way to do so. I've also tried the Web client, but it displays a tablet-specific view, even when I've checked "request desktop site".
How can I view SMTP headers in the Gmail app?
If relevant, the device is an Asus Eee Pad Transformer tablet running on Android 4.1 Jelly Bean.

Sadly there's no such option in the official Gmail app.
You can try using a third party mail client with more options such as K-9 Mail: https://k9mail.app/

Nowadays, there's also FairEmail which does a pretty good job.

It is not possible to view headers in the Gmail app; you will need to open the Gmail web app in your browser instead.
Using Chrome (mobile, 47.0.xxxx.xx) on Android (5.0.2), for example,

Go to gmail.com.

Use the three vertical dot menu at upper-right > request desktop site (not sure this step is necessary, but I did it, and it worked).

Use the gmail menu (three vertically-stacked horizontal bars) to the left, above the main window.

Scroll to the bottom and choose "View Gmail in ... Desktop"

Open the email message for which you'd like header information.

Click Show Original just above the window containing the message body.

The header info will appear.

Well, yes SMTP headers can be seen over the Gmail apps.

Login to your e-mail account (Which I am sure you are logged in over your Gmail app).
Click over the email you wish to see headers on.
On the upper right portion of the message box, you will see a Reply or Reply-to-All button, with a small downward pointing arrow.
Click the small arrow.
You will see the message sub-menu, and an option for "Show Original"
Click "Show Original"

Is that you are trying to do ?

That's the context OP wants, but from with android gmail app, different from the desktop website.


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How can I verify the authenticity of an APK file I downloaded?
The latest update of Google Maps is unavailable in my country, so I downloaded a version by googling for "Google Maps 5.4.0 apk".  I did in fact find it, but now I wonder how I can tell if this is in fact the same version as in the market.
How can I be sure that it hasn't been tampered with? Are apps signed in any way? Is there any way of checking the signatures?

If you visit, from your mobile, the page: m.google.com/maps, does it offer you a download link or something alike?

@Nicolás: It links to the market, from which I can't download it.

related Verify Android apk has not been repackaged?

If you have a second app that is "authentic" and comes from the same vendor, you can compare if both apps are signed using the same keys/identity: Comparing signatures of apks

As long as it's an APK and not an AAB... you can compare the app signature. This just proves that the app has been signed by a developer who generated a key/

Sidestepping the debate over the legitimacy of installing that app on your phone, the question of verification is one that I've been meaning to understand for a while, and you've prompted me to try to figure out a possible way of verifying who signed an apk.
Android apps are signed in the normal manner of .jar files (.apk is really just a special .jar which is just a special .zip) however it may not be trivial to trace the authenticity of the certificates unless you have something known good to compare to.  That's basically what the phone itself does - verifies that something that claims to be from the same party as something already on the phone actually is - the phone doesn't refuse to install things with unknown signers, it can only (object to/clear application data of) apparent forgeries when something new doesn't match something old that it claims to.
You will need to have jarsigner and keytool. I believe these come from the JDK which is a prerequisite to the android SDK rather than the SDK itself.
First you want try to verify the public key contained within the .apk.  Usually this is in META-INF/CERTS.RSA but it can be in another file - unzip -l will tell you.  You want to see what you can find out about it:
unzip -p suspect.apk META-INF/CERT.RSA | keytool -printcert

That's going to dump out a lot of information about who the signer claims to be.  Some certificates are apparently themselves signed by known parties, but without figuring out how to trace that, I suspect you could do something like this:
unzip -p suspect.apk META-INF/CERT.RSA | keytool -printcert | grep MD5
unzip -p knowngood.apk META-INF/CERT.RSA | keytool -printcert | grep MD5

If you have a known trusted apk from the same author who used the same certificate.  I'm assuming that the certificates having the same MD5 sum is enough.
Assuming you've decided to trust the certificate, then you can see if it has been used to sign each of the files within the .apk
jarsigner -verbose -verify suspect.apk

(If there's more than one .RSA file in the archive, you should add the -certs flag to tell you which certificate(s) have been used to sign each file, so you can be sure its the certificate you verified)

@Chris Stratton Is it possible to copy Google Maps apk off a device ? Then one can check the certs as you said.

Recent Android Apps often do no longer contain a v1 signature that can be verified with jarsigner (only a v2 orand v3 signature). Therefore apksigner from Android SDK should be the preferred way to verify a signature of an APK file.

Verifying an APK signature
The correct way to verify an APK file is to use apksigner.
apksigner is part of the Android build tools (Andorid SDK), therefore you may find multiple versions installed, one for each build-tools version installed.
One example path within the Android SDK to apksigner is:
android-sdk/build-tools/30.0.1/apksigner

For more details on how to get apksigner see last chapter of this answer.
Execute apksigner this way:
apksigner verify --verbose --print-certs "Signal-website-universal-release-4.49.13.apk"

Verifies
Verified using v1 scheme (JAR signing): true
Verified using v2 scheme (APK Signature Scheme v2): true
Verified using v3 scheme (APK Signature Scheme v3): true
Number of signers: 1
Signer #1 certificate DN: CN=Whisper Systems, OU=Research and Development, O=Whisper Systems, L=Pittsburgh, ST=PA, C=US
Signer #1 certificate SHA-256 digest: 29f34e5f27f211b424bc5bf9d67162c0eafba2da35af35c16416fc446276ba26
Signer #1 certificate SHA-1 digest: 45989dc9ad8728c2aa9a82fa55503e34a8879374
Signer #1 certificate MD5 digest: d90db364e32fa3a7bda4c290fb65e310
Signer #1 key algorithm: RSA
Signer #1 key size (bits): 1024
Signer #1 public key SHA-256 digest: 75336a3cc9edb64202cd77cd4caa6396a9b5fc3c78c58660313c7098ea248a55
Signer #1 public key SHA-1 digest: b46cbed18d6fbbe42045fdb93f5032c943d80266
Signer #1 public key MD5 digest: 0f9c33bbd45db0218c86ac378067538d
<skipped a lot of warnings>

Estimate the authenticity of the signer certificate
Now you have verified the APK, but you still don't know if you can trust the person/organization who has signed the APK file. This is because on Android APK signatures use by definition self-signed certificates. If you can trust a certificate is therefore a difficult question. The only way is to check the other apps that have been signed using the same certificate.
The only way I know to do so is to use online PlayStore crawling services like androidobservatory.org. It has an API for checking which apps have been signed by the same certificate using the certificate SHA-1 digest:

SHA-1: https://androidobservatory.org/cert/45989DC9AD8728C2AA9A82FA55503E34A8879374

Edit: apkmirror.com also allows to search for the certificate digest. Just enter the plain SHA-1 or SHA-256 certificate digest (without colons or spaces) in the search field:

SHA-1: https://www.apkmirror.com/?post_type=app_release&searchtype=app&s=45989DC9AD8728C2AA9A82FA55503E34A8879374
SHA-256: https://www.apkmirror.com/?post_type=app_release&searchtype=apk&s=29f34e5f27f211b424bc5bf9d67162c0eafba2da35af35c16416fc446276ba26

On this page you can see all the other APK files on Google Play Store that are signed with the same certificate.
Getting and executing apksigner
Apksigner is a Java tool and Google provides for start-up a batch file apksigner.bat(Windows) respectively a shell script apksigner.sh (Linux, MacOS).
As mentioned before it is included in each build-tools version of Android SDK. But it is not placed in PATH so you can not simply open a command-prompt or terminal and execute apksigner, instead you have to manually provide the full path to apksigner.bat/apksigner.sh.
If you don't want to install the whole Android SDK (with or without Android Studio) you can directly download build tools and extract and execute apksigner. Links to the all build-tools are provided on this website (the provided links go to the original Google download locations).
I prefer apksigner from build-tools v30:

build-tools 30.0.1 Linux
build-tools 30.0.1 MacOS
build-tools 30.0.1 Windows

You only need the file lib/apksigner.jar from the archive. Extract it  and open a shell in the folder. Then execute java -jar apksigner.jar.
To execute you need Java 9 or higher (best Java 11 or 17).
Using this direct approach the command to execute apksigner is
java -jar apksigner.jar verify --verbose --print-certs "Signal-website-universal-release-4.49.13.apk"

Or if you use full path names - replace the <..> sections with the appropriate path that works on your OS:
<path to java 9+>/java -jar <path to apksigner>/apksigner.jar verify --verbose --print-certs "<absolute or relative path to apk to be verified>"

For anyone looking to NOT download 1 GB of SDK, this is direct the download link to the (current) build tools: https://dl.google.com/android/repository/91936d4ee3ccc839f0addd53c9ebf087b1e39251.build-tools_r30.0.3-windows.zip

@BorislavIvanov You should mention that your Link is Windows only. besides that there is still the option do download only the Android SDK without Android Studio. Check the section "Command line tools only" here: https://developer.android.com/studio#downloads It contains the SDK manager that allows to download the "Build tools r30" you have linked. In total you end up with about 150MB download.

@kerstin92 Android Studio comes with an installation of Android SDK and at least one version of build-tools, so you should have apksigner installed (but not in the path). You have to call it using the full path to apksigner.bat/apksigner.sh to execute it.

@kerstin92 Just downloaded build tools for API 33 and apksigner.jar is included. So please recheck your installation and make sure you have at least one build tools package of API around 30 installed.

There is (now) an apksigner tool in build-tools that does what you want. From the docs:

Check whether the APK's signatures are expected to be confirmed as valid on all Android platforms that the APK supports:
apksigner verify [options] app-name.apk

Where to download?

(from official/"trusted" sources)

You can also try uploading the APK to the free VirusTotal.com virus checker.  It will generate a unique hash for the APK and if others have already uploaded it to test it (very likely) then you will have more of an idea that the APK is valid.
The service will also scan the APK with over 60 virus scanners and let you know if it believes it has similar signatures to viruses already found.

I wouldn't trust the virus check, as doubt that these anti-virus programs focus on just every Android APK ever distributed. Also, the MD5 will not tell you much, apart from that the same file has been uploaded before.

@Stan - It scans the bytes in the file for malware bytes. It doesn't have to know every APK ever distributed. Also, it's not an MD5, it's a SHA256 and there is a bit of additional info communicated in that if this is the first time the APK has ever been uploaded then maybe it is something unknown and more possibly malicious.  Also, most valid APKs will probably be there. Why not include this as part of analysis as another tool for use? It can provide just another level of confidence or non-confidence about the package. You don't have to consider it the final word, but considering it more data

OK I agree it's useful as an additional source, just not the only one.

To compare certificates from a suspect apk file, maybe one idea is to download it's version on the official Play Store on your phone, doing a backup on your computer and go in the backup directory, select the concerned apk file and do the same checks. You can also view the Google certificates by doing the check on a device-default application (like any com.google.android.* apk)

I'm surprised no one has mentioned this yet, but you don't necessarily need a command terminal to view the certs?  The apk's can generally be opened using open as zip, making it's contents parsable:

You can generally find the certs listed in META-INF > manifest.mf:


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Installing APK via Terminal Emulator
I have installed Android 4.4 through VirtualBox on my PC. I want to know how to install an APK (e.g. FIFA 14) in it via a command in terminal.
How to do that?

$ su

# cd (location in which you have the apk file)

# pm install fifa14.apk (or whatever the apk name)

@agharehanabbas You need to put the actual name of the APK file you have instead of fifa1.apk.

@agharehanabbas You also need to put the correct path after cd, not just (location). For example, if you have put the .apk file in /sdcard/, use cd /sdcard/.

@agharehanabbas inorder to install the apk from terminal emulator you first need to download the apk file. In your case it is fifa14.apk. You need to move the apk file inside your phone sdcard. Then open the terminal and follow the instruction. In cd (location) it has to be cd /sdcard/(folder name in which you moved the apk).


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How can I install pure Android and get rid of bloatware?
I have Micromax Canvas HD 116 with Android 4.2.2 installed on it. What I hate is the unnecessary software offered by them, which is not only occupying space but also RAM and affecting the speed of the device. I just want to get rid of those bloatware somehow.
I know if I follow some good rooting procedure, I can achieve it. But is there any way, or an official way so that I can manually re-install the original pure Android OS on my device?
I would be very much obliged if someone would provide some good resources about it, and which is applicable to any device.

If you dont want to root your device, you can disable the app from settings which stop them from running.

any other way..? just want to get rid of those nasty apps.. and if possible want to install pure android os

If you disable the app they will be no longer visible in your app drawer and they wont run on background which is pretty much what you needed I guess

Go to settings->apps->all, click on the app you need to disable you will see a disable button.

There's no official way to install a "pure Android" ROM: the only official ROM is that provided by the manufacturer.
As sameer says in the comments, you can disable bloatware apps from the settings, with almost the same effect as uninstalling them.
If you want to start from a clean slate, you should look for an AOSP-based custom (unofficial) ROM. Although they aren't always as reliable as the manufacturer's ROM, because they're made by third-party volunteers, for the more popular devices with better manufacturer support they can be very reliable and even better tuned than the original ROM. Start your search at Where can I find stock or custom ROMs for my Android device?

It's worth noting that the warning about removing/disabling system apps on manufacturer-altered UIs should be taken even more seriously than on "vanilla" Android.  Disabling a useless app can have unintended consequences on other, seemingly unrelated areas of the firmware.


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How safe is it to use Aptoide?
As with the latest update to Google Play one no longer sees the full list of permissions requested by an app on install/update1, I feel my privacy is invaded. Even worse, an app could sneak in additional permissions with an update, and without the user knowing2,3.
So I'm looking towards alternatives.
TL;DR:
I know we've got What are the alternative Android app markets?, but a) that's more or less a listing of other markets (without giving backgrounds)4, and b) it's not even mentioning Aptoide.
I don't want another app that has to run in the background permanently to "check license validity", so things like the Amazon Appstore or AndroidPIT are out. AppBrain is just another front-end to Google Play – so nice as it is, it doesn't solve the issue, as for app installs and updates it just has to re-direct to Google Play – which I'm rather about to "flee".
I've already checked out F-Droid a few days ago, and feel it pretty fitting my needs (follow the link for details) – but with just about 1.200 Apps (as of 6/2014) it leaves too many gaps.
Aptoide on the other end is said to serve more than 120.000 apps currently. As the name suggests, it uses APT style repositories, which I'm used to from Linux (Debian and derivates). It even lets you have your own private repo to share apps between devices (or with friends). All apps are offered for free, so no need for a "license server". But how safe is it for the end-user? I've googled (and ducked) for hours, but could not find any source on this. Instead, I found a lot of links of the type "get paid apps for free", "black market", and other piracy-oriented stuff – which is definitely not what I'm after. I'm more than open to paying for good apps5, so "getting them for free" is not the intention behind my question. Like F-Droid, Aptoide has multiple repositories – but I couldn't figure out whether there's a "trust-able" main repository like with F-Droid.
There is related information available in the package description (e.g. this one) indicating safety measures such as malware scan, signature validation, and third-party validation. But as the corresponding web page shows, this information seems to be at least partly relying on user feedback (which could be faked/manipulated), or is not even presented to the user (the package info e.g. names 3 scanners used to check, I cannot find this info on the web page). While I might be able to look things up via package info, I cannot ask e.g. my 70+ years old parents to do so. On this page, Aptoide also points out how to see the results of their security measures, and explicitly states:

Aptoide Anti-Malware platform analyses applications in run-time and disables potential threats across all stores.

(Emphasis mine) – which suggests malware protection comparable to that of Google Play (how does that go together with those "black market rumors"? Maybe they just don't remove offending apps, but only mark them instead?).
So finally
The question:
Is there a way to safely use Aptoide as a source for apps? If so, how?6 If not, why not?
Bonus points for an "idiot-proof" way which could be recommended to less experienced users.

Footnotes
1 I know it would be possible to open the Google Play Store web page of the app, scroll through it, and click the corresponding link when found – but you can't call that user-friendly, or expect users doing this on every update.
2 e.g. on first install it requested the "unsuspecting" READ_PHONE_STATE with the usual justification. With an update, it could request CALL_PHONE, PROCESS_OUTGOING_CALLS, and others – and the Play app would not bring that up, as they belong to the "same group".
3 To figure out "new permissions", one had to compare those of the installed version with those of the present one. Have fun!
4 I've just edited two answers and added some details on AppBrain and F-Droid to fill those gaps
5 I've bought a lot of apps on Google Play (or donated to the dev directly), and e.g. F-Droid has donation buttons on each app's page to make this possible
6 I could imagine by knowing (and restricting your use to) "safe Aptoide repositories" this could be achieved. But as I wrote, I couldn't figure out which ones to consider "safe". The Aptoide article on Wikipedia suggests there's a "default repo" on install, and more repos need to be added manually; so it might be sticking to that first one is safe.

I think an app store is as safe as your trust for the curators or (in the case of an entirely open app store) the developers who submit apps.  IMHO, for Aptoide, I'd put it in the "just as safe as the app devs" category. But that's because I know nothing about the curators interests here.  I would hope that even though they just made it harder to figure out if an app dev is asking more than s/he was for a previous version, Google has a vested interest in not having malicious apps spread across their ecosystem. Not sure on Aptoid's motives.

Thanks for the comments! As for Google Play, I'm not that much concerned for "malicious apps" in the common sense (though several of them slip through Google's control for a while every now and then as well), but rather for "data collectors" and the like (with Google being one of the biggest). And not being sure about Aptoid is the reason I ask this question :) I don't want to replace a problem with another one. And I want to know for sure what I can recommend others.

You left out an important point - does Aptoide even offer an app upgrade process that notifies you of permission changes?  Given the obvious decrease in security and safety when using a decentralized and piracy-ridden infrastructure, it should offer some benefits besides just being not Google.  If you're worried about sneaky data collection, I'd say you're in more danger when getting apps from a storefront with apps uploaded in bulk and not by the developers (and possibly modified).

@ProjectJourneyman Google Play doesn't give such hints on updating (if new permissions are added to "the same group"). With Aptoide, F-Droid, and others being "3rd party markets", they always have to invoke the "local package installer", which shows you all permissions of the app-to-be-updated/installed before you can proceed to install. Though, unfortunately, not a "diff" to the current version.

Thank you for raising these questions. Here is some information about Aptoide that I hope is useful for you and the Stackexchange/Android community:

Malware is something that we take very seriously. Currently, we have 3 different systems to detect malware as they arrive in any Aptoide-powered app store:

we run 3 different anti-virus in emulators in run-time
we have an in-house system of signatures to detect recurring threats
we have implemented a chain of trust based in the signature of the developer

The task of creating a safe environment to the end user is a moving target. We are working with several universities and research centres and in a recent article (not yet published) we compare well with the other app stores. We also proposed a European research project with 2 anti-virus companies and 3 universities / research centres to deal with this topic. There is a lot of work to be done and the feedback of the community is important.
F-Droid is in fact very similar to Aptoide. They are a fork of Aptoide and they maintain all the concepts we developed, like multiple stores. They have a more centralised approach and a central signature which if of course different from our approach.
At Aptoide we have the "Trusted" stamp. If you see the Trusted stamp in an app, we are 99.99% certain that the app doesn't contain a threat to the end-user.

Best,
Paulo Trezentos (Aptoide co-founder)

Thank you very much for your details, Paulo! Though I expected as much, it's good to have these details first-hand. Is there anything to be said about which repositories are considered "safer"/"main" (like the central one in F-Droid – which besides is IMHO the only one using the central signature you mentioned in 3.), to be recommended to the "more cautious user" – or are they all threated similarly? What about those "black markets" Aptoide is related to so often? And is the "trusted" stamp of 4. somehow coded in the XML I've mentioned (to be e.g. auto-detected by a script)?

@all Missing details have been sent to me by mail, parallel to Paulo's post here. Find them summed-up in my answer to What are the alternative Android app markets?

Malware is something that we take very seriously Really? I reported a potential issue via their web-form and after a week nothing happened. See aptoide-how-to-report-potential-abuse-without-becoming-a-member

Thanks for answering here. Can you additionally explain why the apks have different certificates than the originals and why folders like "facebook", "airbnb" or "smaato.soma" are injected into the apks even if the original had no connection to these applications?
I am talking about "trusted" apps, e.g. WhatsApp.

After Paulo's answer, some more mail exchanges with him, I already wrote a detailed description in my answer to another question – and also in an article on my own site: Android Markets: How safe are alternative sources?
Following that, I kept a close watch on Aptoide ever since then, and still do – so let me add a few more details (including some points already mentioned before, for context):

Aptoide is not a "single area for apps" like Google Play or the Amazon App-Store. It's rather comparable to what Launchpad is for Ubuntu: Everyone and his little sister can open their own repository here, which is presented as a "store" separated from the others. There's a global search (for apps and stores), though.
There's only one repository which is "manually curated" by Aptoide itself, called "Apps". Here the Aptoide team decides what apps are entering the repository. Here I …

didn't find a single "pirated payed app", be it for money or for free
checked the signatures of some apps and found them matching those from Google Play for all I checked
don't remember any app without the "trusted" stamp (meaning, the so marked app has been checked for malware with multiple scanners (including Aptoide's own "bouncer"), signatures have been verified to match those of other markets (mostly Google Play), and more – see my already mentioned other answer for details on this)

So my conclusion is in fact it is pretty safe to use this repository.
However, I've also taken a look at several of the other repositories – where you indeed can find lots of obviously "pirated apps" (payed apps from GPlay "for free" are always a signal for that). At those places, not only was the "trusted" stamp missing often – but instead I frequently found the "untrusted" stamp – which means the app was probably contamined (details differed; most often I found the signature to be the issue: "it was used elsewhere to sign another developers package" is 99% sure to indicate a "hack").

Summed up: A general answer cannot be given here (that would be answering the question whether "the Earth" is a safe place to live). How safe it is to use Aptoide pretty much depends on your choice of the repository. One is known to be manually curated and, I dare say, as safe as Google Play, Amazon App Store, and others. A few can be assumed as pretty safe – especially if you know so about their owners, and stick to apps showing the "trusted" shield.
Avoid apps not being assigned the (currently green) "trusted" shield, especially stay well clear of those showing the (currently yellow) "untrusted" shield, best also stick to the Apps repository alone – and Aptoide should be a safe place for you.

I consider the Apps repository safe enough to link it from my app lists – next to F-Droid and Google Play.

If "trusted" , i.e. green apps are verified using a signature from Google Play, why is it better to only stick to the Apps repository alone ?

@hulkingtickets because that way you don't risk to "accidentally hit a yellow one". We all have our moments where we are distracted (or "someone else" is using our device).

Aptoide is a known piracy site for Android apps. If you think any site that knowingly distributes pirated software is safe, you are being pretty optimistic.

You should not write something you cannot back up by sources. What you write is like saying "Windows always has viruses", "computer users are hackers", and the like. Have you even read the answer of user64756? There's a curated repository, and there are "private repositories". What comes to the first is controlled by staff – which cannot necessarily said for the latter.

Rubbish. Aptoide has been a pirate site since its inception, and continues to profit from the distribution of pirated software. Claiming that the staff cannot be held responsible for that which they enable and profit from, is semantics at best.

What you write is like saying "Piratebay is not a piracy site." :D

You must know. So please name me only 3 "pirate apps" in Aptoide's "Apps" store (note: the Apps store, which is their main and curated repository – not one of the many "private repositories", where you in fact find many "pirated" apps. (Why three? Once is an accident. Twice is coincidence. Three times is an enemy action. Meaning: One might have "slipped through" – that happens on Google Play often enough as well, without you calling that place a "pirate bay"). No accusation without proof, please.

Don't make me laugh. The front page of aptoide openly promotes pirated products. Going "oh, but this little corner of the site is clean"... yeah, we've heard that one before. Same old "oh, but we torrent sites only link to the material, we can't control what gets posted".

But don't worry. The consequence of the piracy enabled by sites like aptoide and its ilk is that developers will move entirely away from the "paid app" business model, and move entirely over to the much hated in-app purchases business model.

I won't argue with you. I had close contact with Paulo for a while, and I've observed Aptoide for about a year now. They have their own repo with almost 50.000 apps currently, which definitely is clean – and offer everybody to open and maintain his/her own repo, where they cannot vouch for the content. You can report "ilk", and it gets removed – but they don't "go hunting" themselves. // As thieves and Mafiosi use bank accounts, I recommend you stay clear of banks as well – as bank clerks also only check if being told so (sorry, couldn't resist ;) Don't throw the baby out with the bathwater ;)

I recently released my Android app Westward Dystopia on the Google Play store ONLY and within days found it being offered on Aptoide.  When I contacted the company to get the content removed, they told me they would not unless I registered for their service first and opened an account with them.
This is NOT the way a legitimate site is run.  I wouldn't trust them as far as I could throw them.  Users beware.

This is the exact wording in the email I received after reporting the theft of my content and hosting of it on your site:
"To remove the requested application, we need to have the exact Aptoide URL where the application stands and it is not sufficient to send us a string.
1.- Submitting a single URL
We then suggest that you to fill in the Abuse Report that you can find here: http://www.aptoide.com/report/abuse
To submit the form, please register yourself with the same Google Play developer's email and don’t forget to activate your account."

I've cleaned up the comments here.  Thanks for relating your experience, regomar; anyone wishing to discuss it with you should invite you to [chat].


text:
If I use free WiFi in a hotspot, can data be easily sniffed?
If I use my mobile device in a Wifi hotspot, can I take it that it bears the same risks as using a laptop in that data can be easily sniffed and that the mobile device is also open to man-in-the-middle attacks?

It's worth to note that in an open wifi every user can easily read all plaintext other users are sending. However, in a WPA-protected network, even if the access key is "public" knowledge, each computer still gets it's own private cryptographic "channel" which makes eavesdropping from other connected computers a much bigger effort. Still, only way to be actually private is to only use client-server -secured connections (HTTPS), and to be really, really sure use pre-stored remote certificates for known sites and use some method to get alerts about certificate changes.

@Ilari Kajaste - How do I get access to pre-stored remote certificates for known sites or can I download them to the mobile device?

Personally, I consider spoofed certificate MITM scenario rare enough to be safely ignored. That said, for desktop there's a Firefox extension called Certificate Patrol. Using that, you can first just visit all of the sites and after that the extension will inform you if their certificates have changed. However, I don't know if there's something similar available for Android.

Not quite an answer, but there's an app called WifiKill that can redirect traffic to your phone if it's on the same network, and "kill" the internet connection. So, I guess it wouldn't be harder to just "sniff" the data if it's not encrypted. http://forum.xda-developers.com/showthread.php?t=1282900

See also: Security risks of open Wifi and What Android sync'd data is encrypted? which both have lots more on the security risks of open wifi

Yes: Can other people on an encrypted Wi-Fi AP see what you're doing?

Yes, you are subject to the same risks as you would have in a laptop (or any device that connects to a wireless network, for that matter); to avoid them, the standard security procedures apply: do not use unencrypted connections that you do not trust and always prefer HTTPS for browsing.

Would the same principles of security apply or are they different?

The same principles can be applied for any device that connects over wireless: use only HTTPS web pages, don't use untrusted wireless networks etc...

Yes. There are 2 different problems:
A. An attacker sniffing and/or redirecting all traffic via arp-spoofing.
Two different android applications already do this (banned from market of course). Please note that it might be illegal to install and test them in your country!

FaceNiff allows (don't know if it still applies) to snoop on logged in credentials and take over facebook accounts and similar.
Droidsheep does effectively the same

B. An attacker impersonating as the Hotspot.
The more serious one, I suppose. It allows to hijack your phone any time if you previously have connected to a well known hot-spot provider.
Your android phone usually remembers known hotspots by the accesspoints ESSID alone (it's name) and tries to reconnect to it any time it sees such an ESSID again for ease of use. This allows an attacker to set up such a well known ESSID and your phone will happily connect to it then. Because no arp-spoofing will be involved, you cannot detect this behaviour easily.
Just try it yourself, set up your phone as an unencrypted hotspot device using a well known hotspot ESSID and see how many connections you get in no time... It's maybe not even illegal to use such an ESSID and noone is tricked into using your connection either.


text:
How can battery usage of Android be at 79%?
Till last night everything was kinda balanced.....most of the different parts of the usage were in between 20-35 %, but this morning after having activated the internet from my network provider, it all got unbalanced.
Now Android usage is at 79% and the rest of the things are at a very low usage (between 3 and 7%).
What can be causing this? GPS is off

The total of all the usage should always approximate 100%. That Android (the core) is responsible for 79% of the entire drain isn't anything to worry about, it just says that not much else was drawing power.


text:
Unable to open copied files from computer to device (mount  as disk drive) - HTC Desire S
I connected my phone as a disk drive and put some files ( .png ,.jpg ,.swf ) in the sdcard.
I am unable to open those files on the phone.  I am unable to find those files in the gallery of the device, either.
When I checked details from Astro file manager it is showing the extension .cp$ on all the file, as in filename.png.cp$
I am not getting what is the problem??

The transfer was probably corrupted.  The problem is probably with the host OS, and not with your phone.
What OS and what program were you using to copy the files?  Did you remember to "eject" the phone from the computer to make sure everything was synchronized?
Are the files on the phone the right size?  If you plug the phone back into the computer can you look at them successfully there?  (Or try copying them off and looking at the copies.)


text:
Broken Screen + Using adb shell to run vnc server
I have an HTC HD2 with a completely busted screen, I tried repairing it with a replacement screen but broke the ribbon cable to the screen (oops) sad day,
I've got two of these and I've been running them as servers and ipcam cameras.
I started using qtadb, which did work on my phone despite a broken screen. I installed droid VNC Server beta using the file manager on qtadb.
I grabbed the app's manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest android:versionCode="52" android:versionName="0.991" package="org.onaips.vnc"  xmlns:android="http://schemas.android.com/apk/res/android">
    <uses-sdk android:minSdkVersion="3" />
<application android:label="droid VNC server" android:icon="@drawable/icon" android:name="MainApplication" android:debuggable="false">
    <activity android:label="@string/app_name" android:icon="@drawable/icon" android:name=".MainActivity" android:launchMode="singleInstance">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity android:label="Preferences" android:name="preferences" />
    <meta-data android:name="com.mobclix.APPLICATION_ID" android:value="1F34160B-63BB-4854-BDB7-D46B7EADBF06" />
    <activity android:name="com.mobclix.android.sdk.MobclixBrowserActivity" />
    <service android:name="StartAtBootService">
        <intent-filter>
            <action android:name="org.onaips.vnc.StartAtBootService" />
        </intent-filter>
    </service>
    <receiver android:name="StartAtBootServiceReceiver">
        <intent-filter>
            <action android:name="android.intent.action.BOOT_COMPLETED" />
            <category android:name="android.intent.category.HOME" />
        </intent-filter>
    </receiver>
    <service android:name="avncservice" />
</application>
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
<uses-permission android:name="android.permission.ACCESS_SUPERUSER" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.GET_TASKS" />
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
</manifest>

and I have tried several things to start and run the service using the console on qtadb. I have tried running:
am start -a android.intent.action.MAIN -n org.onaips.vnc/com.mobclix.android.sdk.MobclixBrowserActivity

am start -a android.intent.action.MAIN -n org.onaips.vnc/org.onaips.vnc.MainActivity

am start -n org.onaips.vnc/com.mobclix.android.sdk.MobclixBrowserActivity

am start -n org.onaips.vnc/org.onaips.vnc.MainActivity

am startservice -a android.intent.action.MAIN -n org.onaips.vnc/com.mobclix.android.sdk.MobclixBrowserActivity

am startservice -a android.intent.action.MAIN -n org.onaips.vnc/org.onaips.vnc.MainActivity

etc....
I test each time by NMAPing my device's ip address, no new ports show up. (I don't have a firewall)
But on a working phone, it doesn't start when you run the app; it starts when you press the run button. So How do I press the run button with a broken screen?
I just need vnc server to run so i can actually do some config things to run debian and my video server on it.

Use adb shell am start -a android.intent.action.Main -n org.onaips.vnc/.MainActivity outside the shell, and the VNC server will start.

Vysor is the answer! It's a Chrome app with a built-in VNC server that launches automatically. It even works on Android 6+. Find it here.

This answer was suggested as an edit by an anonymous user, but should stand on its own.

First you have to locate the droidvncserver executable file on your device. On a Nexus S it's in this directory:
/data/data/org.onaips.vnc/files

Then you have to set the execution right on the executable file (it's a UNIX subutility) from PC using adb.exe. In a command line window (from the appropriate Android SDK folder) you can type :
adb.exe shell chmod 766 /data/data/org.onaips.vnc/files/androidvncserver

(this has to be to done only once, for further detail on chmod command type man chmod in google)
Then you'll be able to launch vnc server directly from your PC using adb.exe:
adb.exe shell /data/data/org.onaips.vnc/files/androidvncserver

Additionnaly to connect your VncViewer using the USB cable type in another command line window:
adb.exe forward tcp:5901 tcp:5901

adb shell
cd /data/data/org.onaips.vnc/files
chmod 766 androidvncserver
androidvncserver

No explanations, nothing! Care to elaborate more about this for the benefit of end user reading this?


text:
Bluetooth headset in-call volume doesn't change?
I have a Motorola Droid (the original, A855) and a Jawbone Icon bluetooth headset. The headset does not have its own volume controls, so I've tried adjusting the volume using the volume rocker. While the on-screen display shows BlueTooth volume as what's being adjusted, the volume seems to be exactly the same when turned all the way down or all the way up.
Is this just an issue with the Icon, the Droid, or am I doing something wrong?

Try updating your Jawbone's firmware and see if that fixes it.  You can also try installing Jawbone Companion and see if that helps.  It doesn't have the OG Droid listed as being compatible when I click on Install on the Google Play site, it has my OG Droid as one of the options so it's worth a shot.


text:
is it 100% safe to install Custom Roms
I wonder if is possible for those people who download the Android source code and customize it then release their custom roms to hack the API or any other part of the codebase like GMail client or network stack so to push in the rom some kind of spyware, virus and so on...
my main concern is that I like to experiment custom roms made available by any developer online but I really would not like to get my traffic sniffed or my Google Account pwd stolen.
Any idea? is Android safe by default in this way or could it be altered?

No piece of software that you install on any hardware of any form is 100% safe unless you are the author or you've read all of the source code, verified its safety, and built it yourself. Okay, so this may be something of an oversimplification, but it's actually not too far off in most cases.
Custom ROMs are no exception to this. Yes, a ROM author could put spyware, a backdoor, or just about anything else they wanted into a ROM if they wanted to maliciously exploit it. With AOSP ROMs I suppose the possibilities are somewhat magnified since the Android source itself could be modified to contain some kind of exploit or spyware.
It's also worth noting, however, that running a manufacturer stock ROM isn't necessarily a safer option if you're concerned about privacy.
The question "is Android safe by default" is in some ways kind of a meaningless question. Is it designed to be safe? Well yes, data is protected at the application level and apps are sandboxed. Any OS is intended to be safe, but all of that goes out the window when you run a ROM that's not pure AOSP. On top of that, the nature of code is that it has bugs, with Android being no exception. Custom ROMs and manufacturer ROMs alike can absolutely have the potential to introduce (either intentionally or unintentionally) ways for your data to be sniffed or stolen.

This is one reason why open source has such high value.  You know exactly what you're getting and you can help fix problems if you find them.

Is anyone aware if TeamNexus' NexusOS roms are safe? https://github.com/TeamNexus

While this question is not often asked, it is one of the best concerning Android safety out there. Custom ROMS are not safe at all. Ise only official firmware and OS.

It's very interesting that you should recommend avoiding custom ROMs because they might contain spyware, and using official ROMs instead, when  several are known to contain spyware.


text:
How to root my HTC Thunderbolt?
How can I root my HTC Thunderbolt?

Please don't vote to close this questions as duplicate.

There's a forum post at xda-developers  which details a fairly involved and definitely for the faint at heart. However, do not follow that guide, it's included only for posterity, and there is an easier way to skin your particular cat.
At this point, cue the huge disclaimer that a lot of things might go wrong when doing this, and always be sure to follow the instructions as closely as possible. When in doubt, ask. Also, while this guide probably won't change much between versions of the recovery tool, always read the official documentation first and use this as a handy checklist.

Revolutionary
Whiskey Tango Foxtrot is Revolutionary?
Brought to you by the same guys that worked on unrevoked and AlphaRev which have been traditionally used to root HTC devices, Revolutionary is a new S-OFF and recovery tool for next-generation devices.  The list of currently supported devices is here.
Okay, what do I need to do?

Download Revolutionary. Versions for Windows and Linux are available.
Windows users: Download and install also these fastboot drivers.
When downloading, also request a beta key. Select your device type, and put in your serial number.
If you are running the stock ROM, your device S/N should be in Settings->About Phone->Phone Identity->Device Serial Number. If you are running a custom ROM, this number might not be there, so you can either check the box your device came from, or (better) find it on a sticker below your battery. It's a good idea to also write this down somewhere for future reference.
You can find the HBOOT version of your device, in case there are several, by booting it into recovery mode: turn your device off, then turn it on while holding simultaneously the Volume down key and the power button. The HBOOT version should be visible somewhere on the recovery screen.
Okay, now you have everything you need.

Make a backup of your phone. No, seriously, MAKE A BACKUP of your SD card and any application information you'd like to keep. Contacts, SMSes, and everything you can think of. Better safe than sorry. There are free tools on the Market that can help you.
If you are going to install custom ROMs, now would be the time to copy them to the device's SD card.
Extract the Revolutionary archive in a convenient location on your computer, and run the executable (revolutionary or revolutionary.exe, depending on your platform).
Connect your device to the computer. Remember to enable USB debugging when doing so (Settings->Applications->Development).
When prompted for the beta key, supply what your key, and then follow the instructions on screen (basically, confirm a few times that you do indeed know what you are doing). It might take a few minutes, and your device will reboot a few times.

It worked, and my phone's not even bricked!
Welcome to the club! Flash a snazzy new ROM like a king, and enjoy responsibly your newly-gained privileges. Some things you might want to do, though:

Before doing anything else, make a backup of your stock ROM from the recovery mode, in case you'd like to restore it later (for example, to take advantage of the device warranty, or when selling it).
If you are only after a root without installing a custom ROM, then you'll also need to install the Superuser application from the recovery. If you'd rather flash a custom ROM, you won't need this, most ROMs also includes Superuser as a part of their base install. For information how to install your ROM of choice, consult the documentation supplied by the ROM vendor.

The HTC Thunderbolts recently received an upgrade to Ice Cream Sandwich. This wouldn't have any effect on the effectiveness or safety of the method above, would it? I imagine not, since rooting must be independent of the O/S, but as someone just beginning to look into rooting, I'd rather be safe than sorry...

@acheong87: This answer was written more than one year ago. Most of the stuff should be still relevant, but do verify the information here before trying to root your phone. Good luck!

I have HBoot 1.08.000. The revolutionary tool only gives keys for up to 1.05.000. Am I stuck with a non-root phone (I was able to get the bootloader unlocked)?


text:
Are the apps safe? How can I make my Android more secure?
Are the apps on the Android Market checked or audited?
If I search Google for "hardening Android", the best hit I can find is Google Android Hardening Checklist.
What's your opinion regarding this? Is there a way to make Android safer or more secure?

Google added a new security layer to the Android market in February 2012.

Adding a new layer to Android security
  Today we’re revealing a service
  we’ve developed, codenamed Bouncer, which provides automated scanning
  of Android Market for potentially malicious software without
  disrupting the user experience of Android Market or requiring
  developers to go through an application approval process.

For further information read here: http://googlemobile.blogspot.com/2012/02/android-and-security.html
Android 4.2 has added extra security with a setting that allows Google's security scanner to (optionally) scan all of your non-Market (ie side-loaded) apps for malware too.

The feature is an extension of the security technology Google
  introduced for the Play Store this past February. While that
  technology worked exclusively on the server side, analyzing apps that
  were uploaded to the Play Store, the new system works with your device
  and scans any apps you install from third-party sources (a process
  known as "sideloading").

(ComputerWorld: Inside Android 4.2's powerful new security system)

It only takes a one time fee of $25 for a developer to start putting apps on the market.  No hoops to jump through.  $25 and you can publish as many applications as you want, instantly.  No waiting, no queues, no approval process, nada.
However, there have been a few cases of malicious applications. When these problems arise, Google usually pulls them from the Market (and from user's phones).  It doesn't happen very often.
Android was designed to to keep yourself protected: all applications have to ask for "permissions" to do certain things: make calls, read contact data, access the internet, etc.  Read the permissions before you install an application.  Make sure you know and understand what it is going to be doing.  Does it seem to have a dubious "permission" that it asks for access to?  However, at the same time: don't berate the developer because of certain permissions.  Some ads ran in apps require at least the internet permission and sometimes some other ones (about the phone state, I believe). Be sure to have a thorough understanding of why a developer would need certain permissions.  Most importantly, read what other people are saying about the application in the market.  Read some of the comments (although beware that the comments on the Android market are the same level as Youtube in terms of quality) and see what the app's rating is.  Have you heard of the app before?  Has a blog mentioned or reviewed it?
Worse case scenario: if you aren't rooted, then no single application should be able to damage your phone as every application is sandboxed from each other (technically, each developer's set of applications are sandboxed from each other. Apps signed by the same developer key can have access to other apps signed by the same developer). They could potentially steal your data, depending on the amount of permissions the application is given. The rarest scenario I can think of is if an application uses an exploit to enable root access on your phone and then does something malicious (e.g., delete everything).

They designed it badly: the system is crippled by the inability to deny a privilege (still beats desktops though...)

I do not believe anyone from Google explicitly audits Market apps.  They probably run some checks now to look for known malware (edit: yes, see Leandros' answer) and that sort of thing, but Android apps do not have an approval process like iOS apps.  See http://en.wikipedia.org/wiki/Android_Market#Application_security
The best way to keep your device secure is to make sure others never have access to it, and to make sure you only download apps you trust.  Android uses a Linux-style kernel and has a tightly sandboxed security model, so as an OS it's very safe in and of itself.  You mostly need to protect against user error :)

No platform is 100% user-proof, so exercise caution and common sense in the same way as you do on your desktop -- you probably wouldn't install some random program on your computer that you heard about on a website without some prior research, even with an antivirus program/latest updates installed.
Same rules here -- do yourself a favour and find more information about the program you are interested in and its developers. Market comments are usually a good place to start, but perusing other Android-related sites won't hurt either,

Assuming you're in the US, the new, just launched Amazon Android Appstore does check and audit the apps before they're put up on the store, so should be a safer place to get your apps from.
From their Developer FAQ:

Our goal is for Amazon Appstore
  customers to have a good experience
  with every app they buy from the
  Appstore. As a result, we will be
  testing the apps you submit prior to
  making them available in our store to
  verify that each app works as outlined
  in your product description, does not
  impair the functionality of the mobile
  device or put customer data at risk
  once installed, and complies with the
  terms of the Distribution Agreement
  and our Content Guidelines.

However, as they've only just launched this week, they don't have any long term record that we can look at to see how effective their screening is, and what they do if an app does slip through their process somehow.

If you are worried about people getting a hold of your device and using it, you can add a passphrase, code, or swipe gesture to keep people out. If you are worried about the data within individual apps once the phone is unlocked, Protector does a nice job of blocking access to a list of apps you specify, enter a PIN to unlock.

There are antivirus products like AVG and Lookout, but I don't think they detect spyware. Google Market itself is really risky, since anyone in your account can remotely add any app, and some security holes have been found and patched. Best thing to do is check an app's permissions when installing, and use antivirus and firewall such as droidwall for privacy.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/2.5/


text:
Why does my Nexus S not see the Jelly Bean update?
My Nexus S is running the stock "soju" build of ICS from Google (build IMM76D). However, I have not seen the OTA update for Jelly Bean. Am I running the wrong version? Do I need to change some settings? Or should I expect the device to see the update soon?

You can try forcing your device to ask for a free download slot:

Settings > Apps > All
Find Google Service Framework in the list, tap on it
First tap Clear Data, then Force Stop

After this procedure the last checked date under Settings > About Phone > System Update should have been reset to 1970 or so. Tap the Check now button there and see if the update notification pops up now.
If this fails even after multiple tries, you can follow a slightly longer procedure described in this post, which involves taking out the SIM card.
Apart from that, you could just wait (you'll definitely get the update with your current config) or flash it manually.

I tried that; it still didn't see the update.

As I said, just a try not a guarantee although many users had success after doing this procedure multiple times. But, as the other comment points out, the rollout also depends on your carrier because Google doesn't roll it out at the same time all over the world but rather carrier by carrier. But there're definitely users with Nexus S on AT&T who got the update: http://erik.thauvin.net/blog/posts/3981/how-i-upgraded-my-att-nexus-s-i9020a-to-jelly-bean-android-411

Okay I followed the instructions in that guide, and it worked. I think removing the SIM was what caused it to work. (I suggest putting the link in your answer so more people will see it.)

good suggestion, added another short paragraph with the link. Have fun with Jelly Bean

My hunch is that you will indeed see the update eventually; I think the schedule depends on your carrier.
If you're impatient, you can download it directly from http://android.clients.google.com/packages/ota/google_crespo/9ZGgDXDi.zip, although I confess I was never able to get that to apply; you might also try downloading the entire 4.1 image and running the "flash-all" script; that worked for me on previous releases and thus I assume it'll work for you: https://dl.google.com/dl/android/aosp/soju-jro03e-factory-c9f5a67d.tgz

Why should it depend on my carrier? It's the stock Google image so I thought it got updates from Google. (It's on an AT&T prepaid plan if that matters.)


text:
Why are all contacts grayed out in Google Talk?
I have just noticed that all my contacts in Google Talk are grayed out. I can't chat, see their online status or otherwise use the app. What happened? Any suggestions on how to troubleshoot or fix this?
I have a Nexus S. I don't use Google Talk often, so this is the first time I have noticed the issue. There were a couple of recent events that may be related. A few days ago I received the official Android 4.1.1 Jelly Bean OTA update from my carrier (I previously had 4.0.4 Ice Cream Sandwich). Also, there was a major Google Talk outage that affected most desktop and mobile users.
I searched around and found possibly related reports, but with a few differences. For example, I don't have settings for turning off data usage. Also, I can correctly use Play Store and other Google apps. I cleared the Google Talk cache but nothing changed.

It turns out that I had somehow inadvertently gone offline. I went online again and Google Talk works now.

If you had gone offline then you wouldn't have been able to use the Play Store either?! That google talk outage was bizarre. I couldn't find anything about it in the news, but caused my Google Chrome browser to crash... "googletalk plugin has stopped responding".

I did some tests, and turns out that the contacts are grayed when your phone's APP isn't able to communicate with Google Talk servers.
This is also the behavior when using Google talk on other systems, or even from Google web pages, like Google+.
You didn't noticed this before, most likely because you never had a communication issue with their server, witch is good. I have my grayed contacts all the time :(


text:
Back up sdcard to cloud
Problem: I have an internal flash drive (/sdcard) with "stuff I don't like losing". Due to a bug in ClockworkMod Recovery, it got wiped the other day. I had been manually backing up my entire card to my local computer every so often, but it was a manual process.
I have a Box.com account. I have a Dropbox account. I have a Google Drive account. I want to automate uploading everything to one of those services (preferably Box, as I got in on the 50GB promo they did). I'm assuming this exists as a free or one-time purchase app, but all I can find are "back up services" that require a subscription.  I use Titanium Backup to back up my apps, I take full images of my phone via CWM every so often, but I can't pass all that data to the cloud (well, TiBu will upload to Box/Dropbox, but that's not everything).
Dropbox has a built-in image backup that will automatically upload any pictures I take to my account. Google+ can do the same to my G+ account. However, that's still only a portion of what exists on my internal storage.  I want something that will grab everything else. Ideas?

BTW, if this is a dupe, could someone pretty please point me at an answer? I searched, but all I found were phone data (app) backups and image backups.

If your device is rooted, you might want to take a look at Titanium Backup, which has built-in support for Dropbox, Box and Google drive.
As for your "special folder", I'd say you will probably like FTPSyncX -- which allows you automatically sync with Dropbox as well as with your local PC via SSH, FTP, and others. The latter can happen automatically all xx Minutes when your Wifi is in reach, or when any Wifi is in reach, or generally... And the App is well supported. Alternatively, there is FolderSync, additionally offering support for SkyDrive, SugarSync, Ubuntu One, Box.net, LiveDrive, Google Drive, Google Docs, HiDrive, NetDocuments, Amazon S3 and WebDAV.
FTPSyncX:

FolderSync:

Ouch -- right, missed that part. But that was not the main part of my answer, but rather a "you might also like..." -- as the focus was on syncing the OPs "special folder on internal SD" -- which I don't think is a task TB does care for. So far, you won't bust me as being OT, will you? ;)

I've installed the trial version of FTPsyncX and the lite version of FolderSync, so we'll see how those go. Both look interesting. Thanks for the suggestions!

@NDGeek You're welcome! I'm using FTPSyncX for quite a while now. Though the design is not that nice-looking as FolderSync's, it works fine for me.

@Izzy I ended up ruling FTPSyncX out because it doesn't support Box. FolderSync seems to be working pretty well though. I also discovered that the TiBu people make an app that does this, but again, it only  sends to Dropbox at the moment...so FolderSync it is!

Right, Joel has Titanium Media Sync in the wild. I skipped that in my post as I thought it not close enough to your needs -- and as I can see I was right ;) Glad you found your solution in my answer.

I would recommend you to use SanDisk Memory Zone available from Google Play Store.
Once you have installed the app, run it and it will scan your entire SD card and the internal memory of your device.
After that, choose a cloud storage provider where you would want to backup all the data.

This is close, but I'd prefer something that works on a  file/folder level. It also doesn't agree with my system on which storage is internal and which is external. Thanks, though!

I know this comes a little late, but for the sake of others like myself who stumbled upon this question (in my case, it matches word for word my needs, it's spooky) I found something that suits me well.
https://play.google.com/store/apps/details?id=eu.kowalczuk.rsync4android
It's rsync over SSH and works very well - provided you're already familiar with both.

Link is broken.


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Show battery percentage on Nexus 7 (Jelly Bean)
Is there a (preferably built-in) way to show the remaining battery percentage in the status bar on the Nexus 7 (4.1.1)?

Jelly Bean
Unfortunately, there is no setting that you can enable to show battery percentage on the system icons tray. Without using an app, all you have is:

Battery indicator on the top right corner of your screen.
Access to the battery settings, level and usage details:
Go to: Settings > Device > Battery

App
Using the Battery app by MacroPinch available from Google Play Store, you are able to get the percentage on your status bar:


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Restore contacts from nandroid backup
I got a nandroid backup of a stock android froyo firmware. The device (GT-I9003, Galaxy SL) is now running cyanogenmod 9. how can i transfer the contacts (and sms/mms optionally) from the backup to the running system?

TitaniumBackup pro has an 'extract from nandroid backup' feature