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Moto G doesn't boot anymore, not even into recovery
My Moto G 2013 (XT1033) was working (except for the issue I described here, but the other features all working), I restarted it but it didn't come back.
I was dropped into the 'AP Fastboot Flash Mode' and selected 'Normal Powerup' from the menu, but I get the error message failed to validate boot image.
Choosing 'Recovery' doesn't works, either, I get failed to validate recovery image.
Does that mean my phone is dead for good? What can I attempt?

With fastboot being the only thing that works (and the boot-image borked), it looks like the only chance left is to flash a ROM. For a starter, check with our fastboot tag-wiki, and also see Where can I find stock or custom ROMs for my Android device?

This may be a bit late however I think I have found the solution for my Moto e 2nd gen (XT1524).
If you found that you can't boot because 'failed to validate recovery image' read on.

Download drivers + adb + fastboot (Download standalone version to PC)
Ensure fastboot can find device fastboot devices
Download TWRP (https://twrp.me/) place in folder
Use command fastboot boot [path to recovery].img
You should now boot into TWRP (yay!)
Download a rom and move it to the device (with GApps and any other additions) using command adb push [filename].zip /sdcard/ (or to anywhere you want to flash from)
Wait for the files to move over (this will take a while)
Backup files (as your system is pretty much kaput not much need to backup the system)
Select wipe, advanced wipe, and wipe cache, system and data partitions then swipe to wipe
Select install, navigate to /sdcard/ (or wherever else you put the files)
Follow the onscreen prompts to install (INSTALL ROM FIRST THEN GAPPS AND ROOT)
Finally reboot into the system (THIS WILL TAKE 20 MINS + LEAVE YOUR PHONE DON'T TURN IT OFF KEEP IT PLUGGED IN)

You should now have unbricked your device.


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How fix sd card unexpected unmounting on Lg L65 (kitkat)?
I have bought sd card Kingstone  which supports UHS-I standart and use it with Lg L65 mobile phone (android 4.4.2). Of course I moved almost applications to it. Everything works just fine and fast, but every ~2 days I see a message that sd card was removed or has unsupported file system. I have to turn off (not restart) and turn on my mobile to make sd card working again.
Is there a way to fix such problem?

Take out your SD card, then put it into your computer. In Windows, go in and check for errors. Then format the SD card, but make sure that you back up any information on the card that you do not want to lose

How to "check for errors"?

source: Stack Exchange

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

sort: votes


text:
Samsung Galaxy S5 missing Sinhala fonts after Lollipop update
I have upgraded my Samsung Galaxy S5 to Lollipop recently. Now I am unable to see any Sinhala fonts. Any fix for this?

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


text:
Sony Xperia Z ear speaker is stop working during calls?
In my Sony Xperia Z the ear speaker stops working during calls. When I press the top of the phone where the ear speaker is placed, it starts working but after sometime it stops working again.
Can someone tell me what's wrong with my phone?

Sounds like a faulty speaker.

Is there any way I can fix that?


text:
Completely exporting a WhatsApp chat, including media and voice messages
I have a chat with a lot of voice messages, pictures and chat messages that I would like to completely export to my laptop, so that I can listen to the voice messages, view the pictures and read the complete chat history.
The 'email chat' option only exports a small portion of the text and voice messages and just 8-10 pictures. As for the 'back up chats' option - I don't know what to do with the created files - as far as I understood from googling, they are meant to be read by WhatsApp itself - not by you on a PC/Laptop.
Thank you for any help!
Update:
Kind of a solution: Decoding the WhatsApp encrypted backups - link

user1482714 i wanted to know how to decode the backup if u can help me, thank u in advance

I don't remember anymore but you need some application that can open the db files (or whatever it was that one gets out of it). I used something called DB browser for SQlite for Ubuntu

Not really Android stuff but you can export your chat from WhatsApp Web using this browser extension https://chrome.google.com/webstore/detail/backup-whatsapp-chats/gmbicfpadlmgkfhfepknbmemfhahelll. Will include all the media sent in the chat as well.


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Samsung Galaxy S3 doesn't mount external SD card
I've recently flashed the stock firmware onto my Samsung Galaxy S3 because there was one feature which didn't work on CyanogenMod. My external SD card worked fine until recently - the 'mount SD card' option in Settings is now grayed out, and whenever I insert the SD card into the device, the following messages appear in the logcat:
W/MountService( 3370): Failed to mount media on insertion
W/MountService( 3370): java.lang.NullPointerException
W/MountService( 3370):     at com.android.server.MountService.doMountVolume(MountService.java:1212)
W/MountService( 3370):     at com.android.server.MountService.doMountVolume(MountService.java:1288)
W/MountService( 3370):     at com.android.server.MountService.access$2100(MountService.java:134)
W/MountService( 3370):     at com.android.server.MountService$6.run(MountService.java:1021)

My computer seems to recognise the SD card just fine. Can anyone help me with solving this problem?
Update 1: I was successful in mounting the SD card manually using the shell command from this tutorial: http://forum.xda-developers.com/showthread.php?t=1804573, however it was only accessible to apps with root permissions.
Update 2: As suggested in the comments section, I formatted the card in question to exFAT. The problem persists.
Update 3: The dmesg (/proc/kmsg) file seemed to have some relevant information. This is what got logged into it when I removed then inserted the card:
<6>[ 5096.384848] c2 mmc1: card removed.
<6>[ 5096.385093] c0 mmc1: card e624 removed
<6>[ 5096.478613] c0 sdhci_set_ios : MMC Card OFF samsung-hsmmc
<6>[ 5097.221780] c2 mmc1: card removed.
<6>[ 5097.221830] c2 mmc1: card inserted.
<6>[ 5097.421722] c2 sdhci_set_ios : MMC Card ON samsung-hsmmc
<6>[ 5097.450386] c0 mmc1: cmd 52 command timeout error
<6>[ 5097.450735] c0 mmc1: cmd 52 command timeout error
<6>[ 5097.454610] c0 mmc1: cmd 5 command timeout error
<6>[ 5097.454944] c0 mmc1: cmd 5 command timeout error
<6>[ 5097.455274] c0 mmc1: cmd 5 command timeout error
<6>[ 5097.455606] c0 mmc1: cmd 5 command timeout error
<6>[ 5097.599241] c2 mmc1: new high speed SDHC card at address e624
<6>[ 5097.600105] c3 mmcblk1: mmc1:e624 SU32G 29.7 GiB
<6>[ 5097.614116] c3  mmcblk1: p1

Comments are not for extended discussion; this conversation has been moved to chat.

I fixed the problem just by flashing the stock firmware (using Odin) again. I didn't even have to wipe /data - all my apps are still there.


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Can I restore backups taken from Titanium Backup on a non-rooted phone?
I have both rooted and a non-rooted phones, there are some apps in my rooted phone which I took a backup using 'Titanium Backup' can I restore it on my non-rooted phone using any method?

For better compatibility with non-rooted devices, I strongly recommend taking a look at ADB backups. Start with the hints in our backup tag-wiki and adb tag-wiki to familiarize yourself with this.

It depends on what kind of backup you want to restore. If it's an XML backup (bookmarks, messages, call log or Wi-Fi access points) then you can restore it. In the case of app+data pairs, only the app can be restored (without its data), and that is only if it's a non-system app.
XML backups can be restored by pressing the Menu button, then scrolling down and selecting the option 'Restore data from XML'.
Non-system apps can be restored by choosing their respective entries in the 'Backup/Restore' tab, selecting the desired backup, then picking the 'App only' button from the popup.

You can restore any TiBu backup on a non-rooted device after rooting it ;) (sorry, bad joke). Arielle, could you please [edit] your answer and include how restoring those XML backups on a non-rooted device is done? And also, how to restore the (non-system) app? I know (how) the latter works, but am a bit sceptical concerning the XML part.


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How to charge a phone without it turning on?
I've got Sony Xperia Z2 (phone) and Sony Xperia Z1 (tablet). Every time I put one of them on charging (and pick up from charging for that matter), the device will turn on. I don't like it and I'd prefer it to stay turned off.
How can I cause that?

Does it boot straight to Android or just to some charging animation? If it boots straight to Android, your phone may not support offline charging. Usually your phone needs to make sure that the battery is charged safely (prevent overcharging or overheating), so there has to be some software running.

In the scenario I'm talking about, it's not really booting per se. The device is turned on since before and then put on charge. After a while, it turns off (goes to sleepy-sleepy-mode or whatever it's called). When I pick it up and disconnect the charging cable, the screen comes to live. I want to be able to pick it up without it coming alive.

Have you turned on Day Dream in Settings > Display?

@MANI It was turned off. When I turn it on, it asks what the device is supposed to do but i see no option for "stay dark" or whatever it might be called.


text:
No option to recover password in Lenovo Tab S8 (S8-50)
So I locked myself out of my tab and I can only open it by entering the password (which I forgot). There is no forgot password option where you can enter your google account to get pass the lock screen. The phone has a google account. Is there any way to bring up that menu? I thought all android devices had the Forgot Password? option

Welcome to the Android Enthusiasts! I've just added the locked-out tag to your question. Please start with its tag-wiki, which holds some first-aid and links to helpful posts. Then come back and either answer your own question (when solved), or [edit] it with what you've tried and where you're stuck. Good luck!

I had similar problem too. My solution was to connect it to the computer and did factory reset. If you have root than follow instruction on this link: https://www.youtube.com/watch?v=tVJ7T2oC_Zs
ON SOME DEVICES IT WORKS EVEN WITHOUT ROOT ACCESS
Good luck! - Nik


text:
audio jack issue
I am facing issues with my audio jack: I can only hear on the right-sided earphone. How can I activate both sides? I'm using a Lenovo a7000, in case that's relevant.

Did you try other (good) earphones to see whether the issue persists?

Make sure there's nothing in the audio jack that could be disrupting the connection. Use a can of pressurized air to blow anything out that might be stuck inside. That's always my first action when the audio jack doesn't work well.
Also, make sure twisting the headphones jack or pushing it sideways a little doesn't cause the sound to play properly. If twisting or pushing it the right way sometimes fixes the issue, and you're sure there's nothing stuck in the jack, your phone's jack or your headphones' plug might be damaged.

First, This may be the issue of smartphone jack issue or may be the headphones issue previously.
Second, please check and sure there is nothing in phone Jack or not damaged the jack of headphones.
Third, Also check the wire of headphone may be cut somewhere or damaged.
If above second and third issue is not there then it must be the first case I mentioned above.

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


text:
Can Android devices with NFC be used as POS terminals for EMV Chip-and-pin cards?
I know that Square, for instance, makes payment card readers you can attach to phones in order to make transactions using the mag strip, and they're soon to release a new card reader designed for EMV chip cards, but are these necessary for Android phones?
My understanding is that tap-and-pay using Google Wallet or Apple Pay (or the like) use the same technology and technique to authorize a transaction as EMV chips do. If that's the case, is it plausible that one could create a program that allows the phone to act as the point of sale terminal instead of as the client? If not, please help me understand how these technologies and/or communication methods differ. Thanks!
Edit: I just found out that some EMV chips support NFC while others need direct contact, and that most American cards don't support NFC, including mine.

Most card's chips are readable via the NFC sensor in your phone. There are quite a few apps on the play store that allow you to read card info (ex BankCard Reader). If you are capable of writing your own application you may be able to receive payments via an external API.


text:
Why does the Kernel and Android System/Android OS drain my battery?
3 hours since unplugging my phone, and at light usage it's at 61%. It is the kind of problem I've had with my previous phone, and I have with my current phone, often starting a few months in and intermittently.
GSam indicates that app usage is 88% of it, with Kernel (Android OS) being 38% and Android System being 21%.
I know it is probable that "some apps" are using some OS functions and that would be the culprit.
Seeing it's a problem that hasn't been solved in more than a year, (even in Lollipop) I'm submitting it here so there's a definitive place to show the solution when it's found, instead of checking endless forum threads on XDA. (Hence note the answer must offer some kind of solution instead of "it's impossible")
I am not willing to take stabs in the dark such as disabling Google Now or Location tracking without a definitive proof. I have Wakelock Detector and it does not show anything unusual.
How do I definitely find out which app is responsible for the drain?
Similar questions
Battery draining fast because of Android System - Question regarding an HTC Droid on 4.4
How to troubleshoot overheating and high battery drain in an Android Device? - while thorough, does not address the share of the "Android System/OS/Kernel" items, specifically
Why do "android system" and "androd os" take 30% battery - accepted answer says "we're not there yet", I'm looking for the way or a workaround to get there
What can cause "Android OS" process to use high percentage of battery? - Is from 2011/Gingerbread and discusses possible example causes rather than a solution

+1, 1) Is the battery calibrated? 2) Do you live in a zone where the 3G or LTE connectivity suffers and the device is set to 3G or LTE? 3) What does Settings -> Battery indicates with your light usage (and what's your brightness settings), 4) Try BetterBatteryStats and Amplify to go close for pin-pointing the culprits. // Compared to your case, I did specify my Android device in that second similar question. :)

1,2 : No; 3. The drain is with the screen off. 4. I'll look at BBS, but Amplify, I'm not looking to mess with the defaults

@Firelord 1) happens automatically with that amount of drain. If after 3h the battery is already half down, it's most likely below 20% when re-attached to the charger. Given a full, uninterrupted recharge, calibration is already done. Whether the batterystats.bin file might been borked and showing the wrong culprits is a different issue.

Thanks for putting a good question ,I can help track and find the problem ,I gonna need more info 1/ I need a logcat for a 1 min with screen off 2/ download "kernel adiutor" from the play store open it once and close it then use your phone normally for 3-4 hours then open the app again go the the frequencies table you will find a stat of all the CPU freq used by the phone post the stat you find then I will post a proper fix or at least locate the problem


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How to sync gmail sent only by specific contacts?
I used to be an email-on-the-phone junkie. Then, I read 4 Hour Work Week, which convinced me to un-sync my email (gmail) from my phone (Samsung S3). I started checking my email once per day on my laptop... then once per week. My productivity skyrocketed, and my stress levels went down. Some weeks, I spend less than 1 hour per week reading and returning email.
After 6 months of not having email on my phone, things are pretty good. But, there are 3 contacts (my wife; my PhD advisor; and a key customer) whose email is actually worth reading in real-time. I'd like to sync email from ONLY these 3 people with my phone.
Here's what I've tried so far:

First idea

Configure Android phone gmail to use me@gmail.com
In me@gmail.com, create a label called "Send to phone"
In me@gmail.com, create a rule to tag wife@gmail and advisor@gmail as "Send to phone."
In me@gmail.com, create a rule to forward all "Send to phone"-labeled messages to me.phone@gmail.com
In the Android gmail app, under Settings > me@gmail.com > Manage labels, I was able to unsync all labels (including Primary, Social, Forums...) except for "Send to phone."

But, it didn't work: emails to my Primary inbox (from people other than wife/advisor/customer) are still syncing to my phone. WTF?!

Second idea

Create a new account called me.phone@gmail.com.
In me@gmail.com, set up a rule that forwards email from wife@gmail.com and advisor@gmail.com to me.phone@gmail.com
Use me.phone@gmail.com on my Android phone

But, it didn't work: I like having the me@gmail.com calendar on my phone. I haven't found a clean way to use the me@gmail calendar but me.phone@gmail email account.

Has anyone done this before?
What else should I try?

Give this a shot. http://www.howtogeek.com/171178/how-to-get-notifications-for-only-the-emails-you-care-about-with-gmail-on-android/
It's not exactly what you want, but it should only notify you when you get an email from those contacts. If this does work for ya. I'll edit my answer and detail how to do this, incase the link goes inactive at some point. Hope this works out for ya.

I strongly recommend suggesting things (when unsure) via comments only, and since you're privileged to do so, consider using that privilege. However, if you still wanna go ahead with your style, then by all means, please  quote the content  rather than waiting for OP to provide feedback and then you do the rest of the work.Your current style, if went unnoticed, might encourage others and could possibly lead to increasing amount of link-only answers (considered low quality) on this website. Hope 'ya -> you' would understand. :)

I gotcha. It was late. Sorry for my laziness. Was traveling and was taking a little break from driving. lol

This is on the right track. I also do not want to see messages on my phone that aren't in the Notify Me category. Even when I disable syncing Priority Inbox,  Gmail keeps syncing it anyway.


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How to upgrade my Android from Linux?
Using Asus Zenfone 5, which I want to upgrade to Android Lollipop.
The instructions say that I have to copy the OTA files to my SD card from my PC, but unfortunately I use Linux (ubuntu and mint). I cannot connect to my sd card via the usb cable. Is there any way to copy the files to the SD card from my Linux platform? Otherwise, can I use dropbox to get the file to the SD card somehow?

Have you tried using adb to transfer the files to the phone

Why cant you mount the device in Ubuntu/Mint? I do it all the time. And most of the time it auto mounts it like a flash drive. Are you getting errors while it's trying to connect? But yes, you can use a 3rd party storage to download it to the SD card, such as Dropbox, Google Drive and etc.

The answers given were great but I felt something needed to be added: If you boot into Android, you should be able to download the OTA file directly from your web browser.

Download adb by typing in terminal:
sudo apt-get install android-tools-adb
Setup adb: You'll find plenty of tutorials on internet to setup adb.
Now type this in the terminal:
adb push /path/to/file /path/to/paste
Replace the paths with your corresponding ones

There are many ways to copy the files from PC into your SD card. Simplest is the Android's native MTP mode, which you might be having trouble with detecting the device in Ubuntu/Mint.
Method 1
You can use ADB as mentioned here by Izzy. Setup ADB and detect device on your PC (see Is there a minimal installation of ADB), open terminal and enter:
adb push <SOURCE> <DESTINATION>

where <SOURCE> would be the file location in your PC like ~/Downloads/OTA.zip and DESTINATION would be file location in your Android device like /sdcard/.
E.g.:
adb push ~/Downloads/OTA_Lollipop.zip /sdcard/

Method 2
Some users report problems while setting up ADB in their PC. In that case, see this method by ykasidit.
You would need to install an Android app named MTP-Alternative USB drive. (See Method 4 for its detailed usage.)
Method 3
Use Airdroid which I covered here.
Method 4
If all the above method fails to work somehow, then try my guide here. See Method #1 there for MTP-Alternative's usage, or try my Method #3 there.

Note that all the aforesaid methods would work with Wi-Fi hotspot and USB-tethering.

You can also use a Micro SD card reader if the SD card is detachable.


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Where can I find saved WiFi AP passwords?
I have a WiFi modem and somehow misplaced the password, but my phone is able to connect to it since the password is already save, but clicking on show password dosen't work.
How can I find the password from my phone?

As a thumb rule, always mention your device name and Android version before writing anything in the body.

First of all you will need root acess.
Now download any root explorer app and navigate to:
data/misc/wifi/wpa_supplicant.conf

Within the file you will find saved passwords.

Not that I needed to do this but I tested it and the passwords appear to be encrypted on my rooted Note 4. network={
ssid="DontStealMyShit"
psk=85f82e22102d1568ec1f9af4cfc04bff
key_mgmt=WPA-PSK
priority=3
frequency=2462
autojoin=1
usable_internet=0
skip_internet_check=0
}
network={
ssid="ZomgWifi"
psk=66108eabc875b1269b6f27c375db656892c0dbce103431761a7e23516267080a
key_mgmt=WPA-PSK
priority=4
frequency=5240
autojoin=1
usable_internet=0
skip_internet_check=0
}
Edit: One is for my 2.4ghz and the other is for my 5ghz.

Well this method worked for me and it doesn't have any encryption in it.(I am using Galaxy S-Duos GT-s7562) @jer3my

It's easily to view your password, use this awesome app: https://play.google.com/store/apps/details?id=ihnel.com.wifipassrecovery
Now you can:

View your connected wifi passwords
Backup/restore easily
Share passwords with your friends
This is FREE APP.

As mentioned in the accepted answer, you need to have root access. Then  download an app called Wifi password and grant it root access. It will show all the saved Wifi passwords in your phone.
To make sure that the app is not considered for other purpose(s), the app's author has mentioned:

This app is not a Wi-Fi password cracker. It just shows memorized Wi-Fi passwords in settings.


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What are the required .aar files for aarddict?
I checked their wikipedia english dump which is about 14GB and opening it with utorrent I saw there are 4 or 5 seperate files. Do I have to download them all to aarddict to be functional or can I download just the 2GB file alone? (or one from the bunch?)

Have you considered asking the dev (or the app's community)? They are the best address for this. You could e.g. start checking their issues (could well be someone else already asked), and open your own request if you cannot find anything matching (consider checking the closed issues as well).

Got it! fired up pc and checked the file and saw they all are chunks of a large file. so most popular wiki articles will be my bet.


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Exit from firmware download mode
Can I get out from firmware download mode without downloading new one? I see horrible message:
Downloading...
Do not turn off target!!!

What will happens if I power off my Samsung S4?

If you are not in the process of flashing another firmware, it's safe to just power off your device.

the power should not be turned off during the Flashing.... if there is a progress bar ongoing you must not turn the power off otherwise simply hold the power button or remove the battery to restart... no problem

You can get out of this download mode by pressing and holding Power button for 10-20 seconds while its inside download mode. Alternatively, you can also simply pull out and reinsert battery and start your phone normally. Unless you are flashing a firmware or similar, this wont cause any harm to your phone.


text:
Can I change the bootloader image on my unlocked moto g in an easy way for another custom image?
I have unlocked the bootloader of my moto G 2013 mobile and now I get the warning message and I'd like to change it for a simple highresolution image of my choice.
Is there a really simple way to do it? I am not too tech-savvy. :)

There's pretty much nothing to do with the bootloader that's 'simple', and if you're not careful when changing things to do with the bootloader you could brick your phone. Changing the bootloader image (not the animation) is very difficult, because the image is part of the bootloader, which is (probably) not open-source.

@JoshHolland Ok. Perfect. I wont touch it then. Cheers.


text:
Can I undo the upgrade to Lollipop and go back to Kitkat?
I have updated my Samsung S4 to Lollipop. And I don't like it. I need go back to Kitkat. I thought if I do factory reset I will get back to Kitkat, but that doesn't work, I'm still with fresh Lollipop. How to get back Kitkat?
My actions:

power + volume up+home
wipe data/factory reset
Confirmation - Yes

After restart I got back to Lollipop

You need to flash a KitKat firmware image. A factory reset does not reset the system partition. IIRC you can find most firmware images on sammobile.com

For what a factory-reset does, please see our factory-reset tag-wiki. GiantTree is right, it doesn't touch "system stuff" – especially it cannot "restore" a previous Android version, as that was replaced by your update.

You can downgrade to kitkat by flashing stock kitkat firmware using Odin (the samsung flash tool).
First, download Odin. Then download framework corresponding to your region from here
Install samsung drivers.
Next run odin on your pc and connect your phone while its in download mode (First go into download mode and then connect it. You go into download mode by turning off phone and then pressing and holding Power Key + Home + Volume Down till it gets into download mode. That "Downloading... Do not turn off target !!").
Make sure Odin recognizes you phone, it should say something like "com..." in one of the boxes which would mean odin has detected your phone. If it doesnt, your drivers arent proper.
Next extract the firmware you downloaded earlier using winrar.
Then in Odin,
a) Click the PDA button and choose the file with .tar.md5 extension.
b) Click the phone button and choose the file with modem in its name (skip this step if file not found).
c) Click the CSC button and select the file with CSC in its name.
d) Click the PIT button and select the .pit file (skip this step if file not found).
Make sure that the "Auto Reboot" and "F.Reset Time" check boxes are selected in Odin. At the same time, uncheck/disable the "Re-Partition" option. Click it only if a .pit file is being used.
Then click "start" button and wait a while. It may take sometime. After process is done odin should show "success" and then you can restart phone (may take sometime at first boot. Wait atleast upto 20mins by watch). You will be back to stock android KitKat rom.
Hope this helps :)


text:
Will plugging the Samsung fast charger into a outlet rated 10W/2.1AMP slow down the charge rate?
The S6 comes with a fast wall charger, but how does it work exactly?
I want to plug it into a “one outlet Belkin” with surge protection, that is 2.1AMP for the ome USB port and 10W for the single AC outlet.
Now my question is will plugging the charger into the Belkin slow down the fast charge time?

Not clear what you are plugging into what. Also where are you (so we know what power system country has, it may be important).

@richard In Toronto. I'm plugging the S6 with the included fast wall charger into a  Belkin 1 outlet surge protector which has one regular outlet and one USB port. The Belkin is rated 2.1 Amp for the USB port and 10W for the regular outlet.

amend the question, in preference to leaving a comment.

FYI. You may like to see Quick Charging 3.0 explanation here http://android.stackexchange.com/a/138678/131553

First part of your question How do fast Chargers work
Firstly one needs to understand C-rate or charge rate. Quoting from the linked article

C-rate is a measure that governs at what current a battery is charged and discharged. At 1C, a battery rated 1,000mAh charges at a current of 1,000mAh. In an ideal world the battery would be fully charged in 60 minutes. At 1C, the same battery discharges at 1,000mA.

Normal Charging

Li-Ion or Li-PO (both have same charge/discharge characteristics) -typically charged between 0.5 C to 0.8 C, more often closer to 0.8 C being the recommended rate. Quoting from BU-401a: Fast and Ultra-fast Chargers

The longevity (of Li-Ion batteries), can further be prolonged by charging and discharging bellow 1C; 0.8C is the recommended rate.

Li-Ion batteries go through three stages of charging of battery charging Figure 1 of Charging Li-Ion batteries- Constant Current, Saturation Charge (current decreases), Ready (almost zero current). If you plot current drawn using an app like Ampere while charging a battery from 10% or lower to 100%, you would observe similar graph (you will not see the first stage unless fully drained and measured by proper electrical equipment)

Fast Charging

Essential difference is the C-rate or Charging rate. These chargers typically work by charging at 1 to 3 C rate
When you charge by such chargers, the second stage of charging (saturation stage ) is skipped and the battery reaches the third stage (ready stage) without being fully charged Quoting from this

.... chargers may use the simplified “charge-and-run” method that charges a lithium-ion battery in one hour or less without going to the Stage 2 saturation charge. “Ready” appears when the battery reaches the voltage threshold at Stage 1. State-of-charge (SoC) at this point is about 85 percent, a level that may be sufficient for many users

Is it good for the Battery? No. Figure 2 here graphically shows deterioration in long term battery life measured in Cycles and the graph shows cycles for 3C charging dropping to 400 cycles compared to 500 for 1C ( I have no idea at what C, Your charger works. I Couldn't
locate any OEM information)

Second part of your question Will plugging the charger into the Belkin slow down the fast charge time?

Going by the specs provided by you: Probably No (linking your Belkin model would help as there are many variants going by your description)
USB rating is same as that of standard USB and power rating of 10W doesn't make a difference (chargers will use as much power as required and not more just because outlet is capable of providing more)
You can compare the charging times reported So, We Fast Charged the Samsung Galaxy S6 and This is What Happened here and update your findings in your question to help others

Simple answer: NO.
A Samsung fast charger puts out 2 A at 5 V.  Even if your Belkin unit's output rating is at USB voltage, it's got enough current rating to cover the Samsung's needs.  If it's at 120 V, it's got roundly twenty times the power required (maybe less than that, since most low voltage power supplies draw more power than they supply).
As a confirmation of this, I routinely charge my Galaxy S4 through a USB cord and 12V USB charger rated at 2.1 A, but not made or sold by Samsung -- which I bought because the USB port in my car didn't supply enough current, even with the Samsung's fast-charging cord, to give a net positive charge rate when running navigation software.


text:
What is the content of data/misc/wifi/softap.conf?
I was going through a question about how to find a saved password in a rooted phone and while doing this I found a file in data/misc/wifi/softap.conf. What is the content of this file?

please consider posting a comment before downvoting....(I am not against downvoting but i should know the reason so that i will not repeat the mistake if any).

A .conf file is usually readable by any text file reader as long as permissions are correct.
The said file contains SSID and password of your portable Wi-Fi hotspot. E.g.:
Android.SE  #$#$ANDROID

where Android.SE is the SSID which other users would see when trying to locate Wi-Fi network and #$#$ANDROID is the password they need to enter to connect to your hotspot.
As for the name is concerned, I never researched for it because I know ap → Access point, and I've seen softap term in logcat's output when enabling hotspot.
There are other ways to see the content of this file. In my Android 4.2.1, I can do:
adb shell su -c 'service call wifi 30'

As for the Android 5.0 (CM12), it would be:
adb shell service call wifi 36

The output isn't very human-friendly but it's not unreadable, and you can easily see SSID and password of hotspot.
Edit: For those who might wonder what those adb shell .. commands actually does in bits and pieces, here is a missing piece:

adb shell: you get a remote shell (access to device)
su: to attain root privileges, use if only necessary; -c: is to pass the following command which would  be executed with root privileges
service: it allows you to read and manipulate services running in your system. Enter adb shell service list to see a list of running ones, and adb shell service to see the command's usage.
call connectivity: to call a particular service (connectivity here). Name of services can be found using service list.
36 is the number assigned to a function of the connectivity service amongst many of it, which we're calling here. You can also pass an integer or a string to the function like adb shell service call connectivity 36 i32 1, but it would take effect only if the function has provision to accept such value. Take a look here to see such functions.

Correct! it consists of SSID and password(I couldn't recognize it). Bieng a noob in android development i would like to know about "logcat" and the commandline thing "adb shell ....". By the way thankyou for your response.

@Jasser A quick note: This site is for end-users only, which means all development/programming questions would be off-topic. That said, "logcat" and "adb" is for end-users too, so try How can I get a LogCat?, and as for adb shell: it opens a remote shell on your PC where you can send commands to Android device. More Q/A only on a new question please. :) And do search since your question might be asked before.


text:
permanently decrypt my android
I have encrypted my android.
I now have these problems:

I want to switch on and login:
The system boots, I the primary user, type my password, the system boots, I type my password (This is a pain).
Another user wants to switch on and login: System boots, they track me down, I type my password, system boots, they login.
We don't shutdown: A bad person finds the device and steals my data, because it is not encrypted.

So now I with to undo the encryption. How do I do this?

Device: Hudl2.
Android Version: 4.4.2.

For the third point, that "bad person" still needs a password to unlock the screen. For the remaining part, we'll need at least to know what Android version that (a bit uncomon) device is running.

Added version. @izzy if it where true that the “bad person” would need the password to unlock the screen, to be able to get to the data, then we would not need to encrypt the device. We are assuming that the “bad person” is not playing by the rules. Maybe they open the device and look at the ram direct. Maybe something else.

To "open the device and look at the [storage] direct" (usually with a JTAG device), they need to shut down the device first. Doing so, they'd need to decrypt again. To access it via ADB, they need to unlock the device and "authorize" their computer.

@Izzy If I just pulled the battery, connected a JTAG, and poked around in RAM. I could probably find something. Maybe even the encryption key (Password). You would be surprised how long DRAM can remember stuff with no power, and I would only have to drop the power for less than a second.

I don't doubt that, given enough effort, everything can be "cracked". Question is whether it's worth that effort – for the average user it is not. But let's stop that discussion (this is not a forum, and you don't want the encryption anyway). For Kitkat (which you stated your device is running), turning encryption off entirely should be possible. I have not done that (didn't encrypt in the first place), but AFAIK the process involves a factory-reset. Have to leave the answer for someone else.

See: Ways to remove android device encryption, and also check other answered encryption questions.


text:
Encryt a single user, not the whole device
My android is multi-user. It is crazy to encrypt the entire device. How do I encrypt just a single user's account?
More specifically, the only thing I am trying to protect is my gmail account.
I know it should be possible, as I have such a feature on my Debian Gnu/Linux laptop. It would however require integration with the login manager.

Afraid not. We're talking about "device encryption" here, which – as the name suggests – encrypts the "device" (in this context, the "storage device"). All users have their data on the same storage device – so either you encrypt it or not.
While it's not possible to "encrypt a single user", there are possibilities to encrypt selected files and directories, which might be an acceptable alternative for you.

While this is technically a valid answer to the question, as originally stated. My experience is that these answers are not only useless, but often wrong.

Thanks for the flowers, @richard – but put that way, there won't be any answer. So why are you asking? ;) There is no way to "encrypt just a single user's account". Is that more useful to you? As for the "often wrong": Please prove, not just accuse :)

In Linux, encrypting user data usually involves just using an encrypted partition/container for the user's /home directory. All user data is stored there so the user is reasonably safe. In Android, all user data is stored on the same partition, the /data partition. The user data for apps goes into /data/user/(userid), the emulated external storage into /data/media. The binary files for apps are shared between users and are located in /data/app and /data/lib. In other words: user data can be all over the place.
Theoretically, you could create a partition for each user's data and emulated external storage, encrypt that and set up the mounting points/symbolic links so that all encryption is done transparently.
However, this would require some serious changes to the file system and probably to the ROM and kernel itself as well because the system must have the /data/user/x directories mounted at boot time. I've never heard of a (custom) ROM that does this, so if you want all your user data to be encrypted you'll have to program it yourself.
If your device has a lot of custom ROMs you might be able to download and modify an existing ROM with some boot scripts. This would probably be a lot of work though.


text:
Does Google+ client come preinstalled on Android phones?
Does Google+ come preinstalled on Android phones? Is having it a mandatory requirement on manufacturers to be certified by Google?

Google Plus is not shipped typically as an standalone app but a part of the bundle named Google Apps (GAPPS).
The core of the GAPPS package is the famous app named Google Play Services which is accessible directly by the user in the form of Google Settings.
That said, an OEM isn't allowed to ship Google Plus or any part of GAPPS package, without the consent from Google. Google on the Android Compatibility page has stated that:

Licensing Google Mobile Services (GMS)
After building an [Android compatible device], consider licensing Google Mobile Services (GMS), Google’s proprietary suite of apps (Google Play, YouTube, Google Maps, Gmail, and more ) that run on top of Android. GMS is not part of the Android Open Source Project and is available only through a license with Google.

(Emphasis mine)
See also: Android forks: Why Google can rest easy. For now

To get their hands on GMS apps, OEMs need to license them from Google; and in order for a device to get a license for the apps, it must pass the Android Compatibility Test Suite and meet the Android Compatibility Definition.

Is having it a mandatory requirement on manufacturers to be certified by Google?

I can't answer this part satisfactorily since I'm restricted to my opinion. However you may take a note on the info in the aforementioned link. It has mentioned that certain OEMs are contractually bound to not to produce non-Android compatible devices so as to avoid Android fragmentation which would be inimical to Google's business. The contract itself isn't released for the public view, so you're possibly on your own.
As for the part why the users are being forced to use or at the least have them in their device, you should consider asking your OEM first! :)
Also see: Why do phone makers not let me uninstall their pre-bundled apps?

Edit by Izzy:
as Firelord asked me to include it, I'll append it here:
There's an article on Engadget on the Google Mobile Application Distribution Agreement (MADA), which describes some of the background. Simplified, if a manufacturer/OEM wants to include Google Play Store (which most want), they must not only include a bunch of additional Google apps, but also place them on the main homescreen page. So yes, this is "a mandatory requirement on manufacturers to be certified by Google" – not only for Google+.


text:
How to get emergency mode in LG E455?
I can't boot my phone but I can see the lg logo.
So my question is how to get emergency mode in LG E455?

(Correctly) using  the recovery-mode tag for that: have you checked with its tag-wiki?

According to this link, you can reach recovery by holding the power button and the volume button for a few seconds when the phone is turned off completely.
From there you'll probably be able to reset your phone to factory defaults to make the phone bootable again. This probably means losing all user data stored on the phone. If a factory reset does not help, you might need to download your ROM (=Android version of your phone) from the Internet and install it using the recovery. If you can't do this in your recovery or you can't get it to work, I recommend you contact LG support.


text:
Android browser redirecting malware sites
I was redirected to appsliu, onclickads and some other sites which were reffered as malware when I was surfing the internet using android browserd on my Xperia Z1. I tried clearing data along with cache in flight mode and also formatting my phone. This happened on my brother's phone chrome too. Any suggestion to clear out this problem? I heard that it is something related to super cookies and how can I remove it from my phone? Your replies are highly appreciated. ☺

Your phone is perfectly fine. It's just the online pop-up ads which redirect you to malware sites or to an app page. Just install Firefox and add AdBlock Plus to it as a solution.

Its not the problem inside your phone or your software. Its something that webscripts are responsible for. Many webpages create automatic redirecting ad popups.
There are two ways to deal with this->
1) To use AdBlock Plus or similar like MANI said. Though on personal note, I haven't really been able to get any such AdBlocking apps to work properly on Android. But again, that could be just me doing something wrong perhaps.
2) Change your DNS. You can use alternative Domain Name Server such as Open DNS or Google DNS or any other alternative you prefer. This works by changing your lookup for an ad-server which points to your local machine, hence basically preventing them to do anything to your PC. Additionally, many DNS servers are configured to block access to domains or hostnames which are responsible for such ads.
By the way, here's Google DNS and Open DNS in case you want to use:
Google DNS
DNS 1 – 8.8.8.8
DNS 2 – 8.8.4.4

OpenDNS
DNS 1 – 208.67.222.222
DNS 2 – 208.67.220.220

Also, you do not need to worry about malware. Malware wont affect your android device unless you manually install a malware infected app :)

Fantastic answer! Care to also include how to set the DNS on an Android?

@MichaelNancarrow you can download an application named DNSset which can also change the cell data to change the dns for phone. This at least works for my phone

Thanks sir jaskaranbir. It works after I changed my dns to google's. It is not redirecting to those sites anymore however it redirects me to play store but it bugs me less. Technically it solved my problem as redirection to play store is still managable for me. As for mozilla firefox with adblock add on, I have not tried it yet but will tell you the result after trying it.

Your welcome, glad you were able to sort out (even if at some extend). On side note, you can go to settings-> apps -> play store and "clear defaults" for it. This way instead of redirecting you to store, the webpage will instead ask the app to use for redirecting you which you can easily cancel and hence will not be redirected. The downside is that everytime you open a play store link using browser, it will still ask to use browser or play store market to go to that link.

@JaskaranbirSingh no prob dude. The problem now occurs again and I found out that requesting desktop site will settle the problem. Solution that you suggested once worked but they are not working already

Usually  it has nothing to do with your phone . its because cache server on your ISP. just call them and ask them to activate DNS poison detection.


text:
How do I send a google hangouts sms to my groups from my google contacts?
I want to send SMS to a large group from my contacts & do not want to have to find each person & click on them. How can I just check one box to send to all 40 people in each group?


text:
Zenfone 2 stuck on USB logo
I tried to flash Zenfone 2 but instead of writing droidboot.img I sent an .exe file. And now when I try to get into droidboot (Volume + Power button) the device gets stuck at USB logo.
Whatsoever I found online is related to Zenfone 4|5|6 and not Zenfone 2
How can I access droidboot again ?
(Click image to enlarge)

Wow, this sounds a little bit like a hard brick. Were you ever able to recover the phone?

Long press the power button. Phone will turn off. Then press power button and volume up button simultaneously, till the asus logo appears. Then you will enter the recovery mode. Reboot from there(press power button after navigating to reboot using volum up/down)

I already explained ,there is no recovery mode because I already erased it in a previous attempt7 to rewrite it, but i used a wrong file to rewrite, so the recovery mode is gone and the phone never enters in


text:
Can I play 1080p HD video on a phone which supports only 720p videos?
I have a phone (Micromax A089) which supports any 720p HD video or movie. But when I try to play any 1080p video then the video runs well but there is no sound.
I am using the latest version of MX Player. I also tried many other players but still got the same result.
Is there any way to play a 1080p video in my phone with the help of an app?

1080p video may not be played well because the mobile has limitation. I too face the same problem with some 1080p videos. In my case audio plays very well but video is laggy.

@MANI Limitations of what sort? Please brief us.

OP says that mobile only support upto 720p video. Isn't that a limitation? And clearly it's a hardware limitation. I tried almost every video player in Play Store. MX Player alongside Custom Codec also doesn't seem to work.

@MANI I can assume it's a HW limitation but what does that mean? Brief! Besides, here are the specs for the said device. Nowhere I see it can play videos only up to 720p. Another note, OP didn't say "only up to 720p" but simply said "any 720p" (without any evidence; from experience I take it as) which may or may not mean "up to". Regardless, OP also doesn't seem to know what kind of limitation it is or this question might not have been posted. Would you now brief us what do you mean by limitation?

I would say RAM and GPU. Playing a 1080p videos is like playing real nice games with real nice graphics which requires atleast 1 Gb of RAM and a good GPU unit with great resolution support.

@MANI Most certainly. There is no way the phone would downscale videos it cannot support. Care to answer this one for us?

For awhile there i had issues with MXplayer. Try VLC, works like a charm on lower end phones i tested on.  https://play.google.com/store/apps/details?id=org.videolan.vlc hope it works for ya.

@jer3my Thanks. i will try VLC player and hope it will work. :)

@Sourav try your luck. Vlc player didn't help me.

Your sound problem is most likely caused by missing the codec needed to play the sound. Try VLC player app.

If you are using MX player, their is a button on the top saying 'HW'.
Click on that HW and change it to SW.
This works with me. I have played a 4k video using this setting.
Though it might lag a bit.


text:
Does custom ROMs like Cyanogen need to interact with TouchWiz?
I am running a nightly build of CyanogenMod on my Samsung Galaxy P1000. I have seen that it runs pretty slow and there are some very critical bugs. So does custom ROMs like Cyanogen need to interact with custom application frameworks like Samsung TouchWiz or any other proprietary closed source software ?
Or does it remove TouchWiz during installation ?
If it did it would make sense for the bugs and the stutters.

Touchwiz is Samsung's proprietary UI/framework. So except Samsung stock and Samsung based ROMs, its not present anywhere else (unless manually ported).
Cyanogenmod doesn't use anything related to touchwiz. Nor does it need any of its components to run. So the problems you are facing are merely just bugs inside ROM/system.
And yes, by default cyanogenmod removes everything related to touchwiz including touchwiz framework.
Additional Info: Since you are using nightly, its supposed to have bugs. Nightly ROMs are basically those when a developer updates the ROM features regularly regardless of whether the feature is completely stable or not. These ROMs are basically for people who like to test features early.

During the installation all Samsung pre-installed software is uninstalled and the new launcher is installed (specifically, CyanogenMod uses Trebuchet);
This means any lag is caused by the custom ROM used


text:
ADB (in recovery-mode) gives "adb server out of date. Killing..." followed by "error:closed"
I connect my device to my PC in recovery-mode, when I write adb devices I get:
 List of devices attached
 4d00ededbeaca0bd        sideload

However, when I try to adb shell I get:
error: closed

Most places online suggest to adb kill-server and adb start-server (to re-start the adb), but it doesn't work. adb usb doesn't work either.
   > adb kill-server
   > adb start-server
  adb server is out of date.  killing.
  * daemon started successfully *
  >  adb shell
  error: closed
  >  adb usb
  * daemon not running. starting it now on port 5037 *
  * daemon started successfully *
  error: closed

Also, most online places comment that ADB has issues with each other. However, I only have a single instance of ADB, so I guess that's not the issue. Do you guys have any idea?

You are probably using a stock Recovery. It's obvious you would see such message (error:closed) since adb shell in Recovery means getting full control of the device which OEM wouldn't want, that's why they limit the device to "sideloading". That's just my theory based on three Mediatek devices; I could be proven otherwise. Also, if you want adb shell in Recovery then try a custom Recovery.

Thanks for the answer. Excuse me for my ignorant question, but how do I try an alternative Recovery mode? My cellphone has a screen shattered, so I am trying to "activate the debbug mode" via ADB shell as described in a few pages (just a few shell commands to change a few text files and you are done). I am guessing those people were using rooted phones, which would explain why they never encountered this problem. I know there is the option to compile a whole new kernel (with the debbug mode enabled by default) and then sideload it, but that sounds like way too much work for me to handle.

I see. Which Android version and device do you have? As for the Recovery is concerned, there is no alternate Recovery mode but the Recovery only. If only your device can be flashed with a custom Recovery you can access adb shell. For that, we need to know is the bootloader unlocked, does your device has a support for flashing from fastboot mode, what are other ways to flash custom Recovery in your device without booting into Android OS? // Some terms might be new to you I suppose.

[A] I have a "Samsung Galaxy S4 19500" with "android 4.42".  [B] Fastboot is already installed in my PC (it came with Android Studio). I have no idea if the device has support from fastboot, I will have to google that. [C] However, there is a "bootmode" to install custome OS on the device (is that the same as fastbootmode?) that can be accessed via a  "secret handshake" (downvolume+start+power) [D] To enter recovery mode I use a different "secret handshake" (upvolume+start+power), but I am unaware if there are other ways possible.

Sorry! because I have no experience with Samsung devices. I could try to guide you but that would be shooting in the dark, and you're already in a mess, so it would be best in our interests if I leave now. // I'm aware of some users here who would probably help you out, and for sure resolve this issue. So please wait patiently, and good luck. :)

Ok, no problemo. I appreciate the help.


text:
Is there a way to auto-reply to blocked SMS messages?
I wish to block numbers from text messaging me, but with an auto-reply. I tried every single suggestion here and other places and for one reason or another, they would not do this for me. The built in spam filter, or call reject, won't reply to text messages that are being blocked in it's spam list. I'm using a Samsung Galaxy Avant.

I tried to answer other question on here but did not know any answers

See if the description of Auto SMS Lite fits your goal. I think it's also doable using Tasker but that's just a theory.


text:
Will an LG G3 Beat work on Verizon in the US?
I asked on Travel a week ago about getting a temporary phone for a trip to Europe but my requirements have changed. Now I need a phone that works in Europe and the USA.
I got to looking at the LG G3 Beat, which is listed as a world phone, using the wireless bands GSM 850/900/1800/1900 MHz. But while I was shopping, I noticed that many retailers do not include Verizon on the list of carriers that the phone will work with, even though Verizon has 850 and 1900 MHz GSM spectrum. Some even explicitly say that the phone will not work with Verizon, because -- according to them -- Verizon is a CDMA network.
My attempt at researching has turned up a lot of posts from 4-8 years ago saying that Verizon was, at the time, in the process of switching from CDMA to GSM. I didn't find any definitive "the transition is complete" announcement, but the best I can tell, it seemed like GSM was fully rolled out as of 2014 1, with CDMA still being kept around purely for legacy support until 2021. (Please correct me if I'm wrong about any of this.)
Are the retailers mistaken about the phone not working with Verizon, or am I not understanding something about how networks work, or is the phone incompatible for a different reason?
1 Verizon plans to drop CDMA from phones in 2014 in favor of pure LTE


text:
Mobile data and Wi-Fi turning on automatically in Samsung Galaxy S3
My phone turned on Mobile data and Wi-Fi automatically. Battery also drains very fast. I checked "Mobile network usage", and turned it off for some  apps, but suddenly, I started to receive messages  "Unfortunately,  Google apps have been stopped".
I don't know what happen. What should I do resolve the issue?

As per this Thread problem was solved by below steps:

Go to Menu
Settings
More Settings
Mobile Networks
Connection Optimizer and uncheck Sprint Connection Optimizer

I had the same problem. Data and Wi-Fi automatically turned on at same time, even though I turned it off it turned on again. Then I tried "forgetting" all the Wi-Fi access points which had been scanned and saved by my phone before and then it stopped.

Could you reorganize your answer a bit to fit the OP's exact requirements? I'll help you out a bit.


text:
How can I tell if my phone is locked?
Thanks to a helpful commenter at a previous question, I now know that Starting February 11, 2015, All Four Major US Carriers Will Let You SIM Unlock Your Phone.
But that just raises another question: how do I know if my phone is locked in the first place? Is there some place in the phone's settings menu I can go to determine this, or do I have to get in touch with my carrier and check with their records?

You could try putting another SIM card in your phone and see if it works, if it doesn't, it's locked.

Not a bad idea, but I don't have access to working SIM cards not from my carrier. And the few people I know in the area where I am are all on the same as me.

What device do you have?

authors: كامل ناهي رواشي


text:
Will I lose root access if I upgrade my S5 from KitKat to Lollipop?
Will I lose root access if I upgrade my S5 from KitKat to Lollipop? If so, why?

The update will probably not even work, but if it works, it depends on what is updated. If it's a major system update, it will remove the su binary and remove your root access.

Since the question has mentioned any update method, I've mentioned some possible cases:

Updating via OTA (from the phone itself using the stock updater): In this case you are certainly gonna lose root.
Why? OTA updates uses a stock ROM (.zip) which will wipe the system partition with every thing in it including superSU and su binary.
Updating via Kies: You are certainly gonna lose root.
Why? Same as OTA, Kies  will flash a stock firmware including the system partition and the kernel too.
Updating using Odin PC and a stock untouched firmware: You will lose root.
Why? Same explanation as for Samsung Kies.
Updating using Odin PC and a pre-rooted firmware: Root access will be granted for the newer version, and you will certainly not lose root access.
Why? Well as the firmware is pre-rooted you will flash new firmware and root at the same time.
Updating using a stock firmware via Odin mobile: Now this app has an option called "ever root". Check it before flashing the firmware to root at the same time when flashing because if you do this you will not lose root, while if you don't you will lose root.

Those are the methods I know but they don't account as all the methods available.


text:
HTC 510 is vibrating uncontrolablly
My HTC 510 is vibrating uncontrollably , but there isn't any notification. What to do ? Its becoming very annoying! Please get to me as soon as anyone can, thanks !

Check Settings, Accessibility and ensure that Notification reminder is off.


text:
Share android Wi-Fi
I've seen that there is an option on android thtat allows to share 3g via usb.
is there a way to share Wi-Fi from a  smartphone (XT1032)to another device via USB (the other device doesn't have a wi-fi receptor)?

You may wanna look into this answer

the other device means a PC right?

@Jasser I don't think OP meant PC because it is already mentioned "there is an option on android [that] allows to share 3g via usb" which is explicitly done for PC.

I see @Firelord then bluetooth tethering can be one of the options I suppose

You can try bluetooth tethering if both devices has bluetooth tehering option with them. You can share your 3g and wifi internet via bluetooth tethering.

The "3g tethering" shares whatever Internet connection you're using over USB. So, if you're connected to wifi, tethering will share the wifi connection over USB.
If the wifi disconnects the phone will automatically switch to sharing the 3g connection over USB.
For example, if you connect your phone over wifi, than connect your phone to your PC over USB and turn on tethering, your PC will have access to the Internet.
This might require installing some drivers though, which has your PC will automatically look for... on the Internet, which it cannot reach. So I suggest you install all drivers from the CD that probably came with your phone, or download the drivers on your phone and then install by sharing the phone storage with your PC.
I've used this method myself a couple of times when I was visiting someone with an old (802.11b) wifi receiver and a more recent (802.11n) access point to speed up the wifi (my phone has a better wifi chip).


text:
Text having stroke/outline on Android Lollipop
I have an issue in Moto G 2nd Gen running Lollipop. It shown a stroke/outline on the text for the entire display. I thought it may or may not be an OS issue.
I tried searching this option in Settings to change the style, but I didn't find anything about it.
Is it possible to turn this off?
Here with I've attached the screenshot, what the difficulties I faced.

Screenshots - (Click to enlarge image)

You've (accidentally) turned on "high contrast text" accessibility option, an experimental feature on Lollipop. From Google official support,

High contrast text
This information applies only to devices running Android 5.0 and higher.
High contrast makes text easier to read on your device. This feature fixes the text color as either black or white, depending on the original text color.
To enable or disable high contrast text, follow these steps:

Go to Settings > Accessibility.
Select High contrast text.

High-contrast text is currently an experimental feature, so it might not work correctly everywhere on your device.

Thank You for your support Mr.Andrew, I Follow the step and resolve it. My Device Become Clear Visible Font Appearence. Thanks a lot.


text:
Can't Disable Chinese apps on Samsung Note 3
A relative picked picked up a 'Samsung Galaxy Note 3 SM-N9006' on his trip to China.
It was misbehaving so I did a reset. When it booted I noticed a few Chinese icons on the Home screen. Opening them takes me to a bunch of Chinese porn sites!
I removed the icons and an app called ChatOn but now I have 4 new Chinese apps that have been downloaded and started automatically!
When I Stop and Disable them they come back.
So what do I do? I don't trust the device as it is. What are my choices?
Root it and try to clean it that way? I don't even know how they are being downloaded. Can I trust the factory ROM at all?
Install a different ROM on it?
Thanks.

Device Info:
Samsung Galaxy Note 3 SM-N9006
Android 4.4.2
Baseband: MT6582
Build: JSS15J.N9006ZCUBMI5

You can try to root this by following a thread on XDA Forum

Chances are the factory ROM has the preloadinstaller.apk, and will reinstall any app that isnt installed, forget if it is every reboot or only on the first one. But I would root, install a file browser that supports root, Search for preloadinstaller.apk then rename/delete it. Then remove the apps. That should stop the apps from reinstalling once they are deleted. Hope this helps ya.

Thx. I'll check it out.

@Vic No problem, let us know if it works out for ya. Also as far as if you should trust the default rom, It depends on who built the rom. I have read many stories about people buying what they thought were legit phones from China, only to find out that they are knock-offs and are loaded with spam apps. I find it hard to believe that even in China that porn apps would be installed by default. Lol. Hope this isnt the case for ya, as far as a knock off phone.

Yes I read about the fact that there are clones. I posted another question for that here


text:
I have a Samsung Galaxy S Relay with a physical keyboard; how can I remap a spare key to send Esc?
I have a Samsung Galaxy S Relay running Android 4.1.2; it's an unusual phone because it slides open to reveal a built-in physical keyboard.
The keyboard has no Esc key. It'd be nice to have one, so that I could use it inside Terminal IDE and various terminal emulators and other apps. The Esc key is useful in the Vim text editor, as well as other software which has been ported from Linux to Android.
I'd like to remap one of the keyboard keys which I don't use (such as the voice-search key or the compose-new-email key) to send Escape.
My phone is running stock unrooted Android. But if you would like me to root it or to install CyanogenMod, that is fine.
I'm willing to modify any of the configuration files stored on the device. But I don't want to spend any money to buy a third-party app.
The Hacker's Keyboard is good. But, since I already have a physical keyboard, I want to use the physical keyboard. Cellphone screens aren't big screens; I don't want to spend valuable screen real estate on a virtual keyboard.
How can I remap a spare keyboard key to send Esc?

You might want to consider using this virtual Hackers Keyboard app based on this project. It provides working Tab/Ctrl/Esc keys, and the arrow keys.

Here are some threads from the xda-developers Galaxy S Relay 4G general forum which may be helpful.

"[root]Alternative keyboard layout compilation"
"[GUIDE] How to get good Ctrl and Alt keys in SSH while keeping Fn"

While this isn't for your device, it might work out for ya.  Take a look at this post on XDA.  It talks about remapping keys on the Droid 4, which also has a physical keyboard.
"Remapping Physical Buttons/Adding Alternate Keys"

Could you add the relevant info from the link here? Since you're already aware of the reason for my requirement, please consider fulfilling it. :)

Since Android 4.1 you can do it without root by installing an app that provides additional keyboard layouts (Key Character Map files).
The example of such app could be found here (I'm the developer).
If you don't familiar with Android development and/or don't want to build such app, there is web-app to do it (I'm the developer). It's free and open-sourced.
There is an example of KCM-file that describes Esc to CapsLock mapping:
type OVERLAY

map key 58 ESCAPE

58 is a KEY_CODE for CapsLock key. To make other key act like Esc key you should find the key-code that is produced by that key. There are several Android apps to do it. For example Gamepad tester (note that it uses 'scan code' to refer to a key code). So the KCM-file will look like:
type OVERLAY

map key %KEY_CODE_OF_YOUR_MEDIA_KEY% ESCAPE

UPDATE:
ExKeyMo web app is not available on Heroku anymore. You'll have to run it locally. See the project's page on GitHub.


text:
How can I know if my Asus Nexus 7 is 1st or 2nd gen?
I was given an Asus Nexus 7. How can I tell if it is the 1st or the 2nd gen?

The easiest way to tell is by checking the front and rear camera.
The first gen has front camera only and there is no rear camera. The second generation has both front and rear camera.


text:
Backup/Restore SMS/MMS via ADB on a non-rooted device?
Is there any way to backup/restore SMS and MMS messages using ADB, when the device is not rooted?

adb pull won't work here, as the corresponding database (/data/data/com.android.providers.telephony/databases/mmssms.db) cannot be read by ADB if it's not running in insecure (root) mode
adb shell "cat /data/data/com.android.providers.telephony/databases/mmssms.db > /sdcard/mmssms.db doesn't work either without root access
adb backup for some reason doesn't cover this database on the device I've checked with (empty backup – just the 41 bytes of the backup header in the resulting file)

I especially wonder why adb backup doesn't cover this. If it's for "privacy reasons", then the same should apply to the contacts database – which clearly is backed up.
References:

Can adb be used to recover SMS messages while in permanent “Safe Mode”? covers the same topic – but other than there, I'm not restricted to safe-mode
backup full sms/mms contents via adb (on our developers sister-site) is for a "rooted solution" (and, apart from that, a bit of age: question and answers are more than 3 years old)

So: Any solution on a non-rooted device? Note that I'm NOT asking for an app-based solution. I'm fully aware there are several apps available for this. I specifically want a "shell based solution", to be used via ADB.

Preferably yes (for other readers: preferred solutions don't require anything modified on the device). Consider the device-in-question already reports "insufficient memory", so it's not possible to install something. As the device is also behaving weird in other context, a factory-reset must be performed – so it would be nice to "save" as much data as possible. I was able to backup most things via adb backup: few exceptions, most of them ignorable, but user very much likes to keep SMS which also were not covered.

Hey there! Sorry to bother have you ever a solution to this without root? BTW excelent app list, thank you for that link!

@Gruber No, still didn't find anything. // Glad you like my app listings!

I especially wonder why adb backup doesn't cover this.

It is not that adb backup doesn't want to cover the app com.android.providers.telephony. This app is not much different from any other system app based on its AndroidManifest.xml. The problem is with the flag its developer has declared in the manifest which as a default mechanism for some reason adb backup is bound to respect.
This flag is none other than android:allowBackup="false". It opts out the app from both ADB backup and restore. Google here has to say:

android:allowBackup
Whether to allow the application to participate in the backup and restore infrastructure. If this attribute is set to false, no backup or restore of the application will ever be performed, even by a full-system backup that would otherwise cause all application data to be saved via adb. The default value of this attribute is true.

(Emphasis mine)
Checkout the AndroidManifest.xml of this app for Lollipop version here, or see this evidence for my Android 4.2.1:

There's more to this app. You can't even Clear Data from Settings → Apps → All apps →<THIS_APP> since android:allowClearUserData="false" is declared too, not something we encounter every now and then.

If it's for "privacy reasons", then the same should apply to the contacts database – which clearly is backed up.

It's bizarre, not that you're able to do it but how is your  system even allowing you to do that just with adb backup!
Contacts storage is handled by "ContactsProvider" app which goes by the pkg_name=com.android.providers.contacts. The flag android:allowBackup="false" is clearly mentioned in its AndroidManifest.xml for Jelly Bean (click here to see for the other versions).
Are you using ICS or any predecessor of JB?
I found that this app doesn't have any declaration of that flag for ICS here. You can actually  clear this mystery, since I can't take backup of this app in my JB 4.2.1 as per the definition of the flag, and always gets that 41 bytes backup file.

As for any other method to take SMS/MMS backup/restore using ADB without root access -- all hands up here.

I'm aware that it's that flag. But both, that app and ADB are part of the system – we're not talking about a 3rd-party-vendor here. For clarification: the device I refer to here runs JellyBean (4.1.2). Thanks to your hint, I'll try again with my other devices (4.2 and 4.3). Concerning privacy: there could also be a hint to have the user providing a password. Plus, SharedStorage might also contain "private data" – plus Google assumes I want to sync my contacts/calendars by default when enabling a Google account, instead of asking me (so no way to opt-out if you add it with them already there).

In danger of it becoming a rant: if it's too private to be backed up – why then is it protected against "clear data" as well? "Never attribute to malice what can be explained by pure stupidity" … // So, it it's not possible without root: that only leaves the appropriate Xposed module ("Backup all Apps"). Which again needs to be installed on-device – which I wanted to avoid … Just pulling the database (with root) would be a work-around – but that doesn't allow for cross-device restore (tried that once, was not a good idea as it rendered SMS unusable so I had to reset)

I know @Izzy that you're aware of such simple flag, (you didn't become Pro out of thin air, but by research and experience :) but others looking answers for such simple question probably do not know about it, and all of this info wasn't suitable for the comment. I actually had in mind to write this comment, but forgot that in the end when writing this answer, sorry!

// As for password, while ADB does provide a pass-protected backup, may be Google (IMO) thought that preventing access to sensitive content is a better thing than to allow access which in case of device lost may result in data dump by unauthorized person if USB debugging was enabled by any chance, followed by brute force attack.

// As for  sync, a company usually does nothing for free unless business is involved, and having data of every single user is quite a lot of data for researching, and for clients who may need it, // I don't know about "clear data", only witnessed it in XML so wrote about it,  // Chances are very slim without root, and that means pure dependence on Google Cloud backup in a non-rooted device which many OEMs take care of it by device warranty void policies so that many users don't root at all

-- oh, well, they had it figured since beginning to how to restrict freedom in the name of business, may be something else. I'll report something good (non-rant of course) if I encounter somehow.

LOL to your last comment's last sentence – especially the if-condition :) And maybe we should see what from these comments should be integrated into your answer (minus the ~70% rants both of us included), and then cleanup? I've meanwhile upvoted it (for the background you've described so detailed). Not really solving the issue, I don't dare "accepting" it – though a "not possible since …" is a fully valid answer. Wouldn't be the first time that, out of the blue, a solution to the "seemingly impossible" pops up here at ASE (and to one of my questions).

Let us continue this discussion in chat.

Partial answer at least, covering the backup part: you can obtain your SMS with e.g.
adb ${ADBOPTS} shell "content query --uri content://sms/ --projection ${projection}" > sms.lst

where $projection lists the fields/columns you want to extract, separated by colons. A list that seems to work on multiple devices/vendors/Android-versions which I have tested would be
--projection thread_id:address:person:date:date_sent:protocol:read:status:type:reply_path_present:subject:body:service_center:locked:sub_id:error_code:creator:seen

Similarly you can also obtain your call logs btw:
projection="type:number:formatted_number:numbertype:via_number:numberlabel:normalized_number:matched_number:countryiso:geocoded_location:date:last_modified:name:phone_account_address:lookup_uri:voicemail_uri:is_read:photo_id:photo_uri:post_dial_digits:call_screening_app_name:call_screening_component_name:transcription:transcription_state:block_reason:subscription_id:subscription_component_name:add_for_all_users:features:new:presentation:data_usage"
adb ${ADBOPTS} shell su -c "content query --uri content://call_log/calls --projection ${projection}" > calllog.lst

Want your user dictionary?
projection="word:frequency:locale:appid:shortcut"
adb ${ADBOPTS} shell su -c "content query --uri content://user_dictionary/words --projection ${projection}" > userdict.lst

Format of the output files will be something like
Row: 0 _id=4, field1=value 1, field2=value 2 …

I haven't attempted a restore yet, though (not yet needed, luckily).


text:
PC not detecting Samsung Galaxy Light SGH-T399
I just bought a used Samsung Galaxy Light SGH-T399N. When i connect it to PC, it is not detecting my cell phone, even after installing the Samsung mobile devices driver the window shows usb icon in the notification area of taskbar but nothing appears in My Computer. I also tried kies 2, kies 3 and smart touch but neither of them are supporting my device. I tried it on both windows 7 and windows 8.1.

Check the window device manager to see if it found your device. if not add new device

@cmos the problem was resolved after resetting the device.


text:
Outlook contacts
I have managed to synch my outlook email and calendar with android, but it is not synching my contacts.  Naturally this is a real bore!
I have checked in my accounts settings and it is saying that it is synched, but my contacts are not showing on my android device.
I do not want to do a csv export as I want them to be continually updating - any tips?

They are probably synchronized but not visible in contacts, try looking into Contacts settings something about contacts to visualize, or accounts.


text:
my wifi turns on and off continuously
Well I am not able to understand why is this happening? When I connect to a particular router this continuous state of switching happens and there is no problem with other routers. What are the possible reasons of this? How to avoid it happening?

I edited the question again @Firelord

I had experienced a problem with wifi tethering of my device and this solved my issue.
Go to settings(Data Settings), there may have an app (I am using Xiaomi device and I have Security app which controls this) that restricts data usage for all applications(both wifi and internet).  In that, there is system app named "Android System" which controls wifi and tethering.
Please check whether it provided with data and wifi access.

Please use comments to seek clarifications. With a bit more rep, you will be able to post comments.

@RahulGopi I edited the question


text:
How to enable Soft keys on Xiaomi Redmi 1S?
How to enable Nexus 5 like soft keys(navigation keys on touch screen) on android devices? My device is Xiaomi Redmi 1S running Kitkat OS. And, can it be done without rooting my phone?

Your device probably be using MIUI and I've never touched it in my life. However, in my Cyanogenmod I can enable/disable navigation bar (softkeys) through "Settings -> Buttons -> turn slider for on/off". See if you've such option.

You do mean soft keys, right?

yes.. home, back, recent buttons on screen itself.

Please check user manual Xiaomi Redmi 1S but based on my experience, you have to rooting your phone and install - check this site. download those softkeys collection from there. but make sure rooting your phone first just as we mentioned before. Dont forget to backup your data.


text:
How to stop contacts and recent call log from syncing?
I am facing a problem. My recent call log list and contacts start loading for 30-40 mins or even hours. Meanwhile I cant see any of my contacts. Its very irritaing. Dont know what is the issue. Can anybody figure out what could it be?

If you want to stop syncing the contacts, go to Settings->Applications->System->Google Contacts Sync->Disable->OK.
I had a similar problem wherein I got force close warnings every 3-4 seconds.
If more than one apps are syncing your contacts then you must also uncheck those features from Accounts group in Settings.
Or you can just turn off background data.


text:
How this "voice dialer" shows up?
Sometimes I'm listening to music on my phone (running Android KitKat), and from my pocket the phone make a sound and the first screenshot shows up and then the second one appears:

Click image(s) for larger version
What makes this shows up and how can I stop it?

Are you accidentally activating the voice dialer by your pocket movements? The same way you can pocket dial by mistake.

@Huey yes, but I don't know how this is activated... is it a button?

The Google Now assistant can be activated by long-pressing the button of the earphone, looks like you use the buttons to control music, but is pressing it too long.
Another thing that could be, are you using original earphones? Some earphones, because of incompatibility, keep sending commands even though you are not pressing buttons. Use another earphone for a day and see it the problem occurs, if it doesn't, the problem is in the earphone.

Yes, I do think it's something with the earphones... If I simply move the earphones sometimes it will crash/close my player app also.


text:
Google Play downloads last forever
I have been trying to download several apps from google play. I've got a 3G tested connection but whatever I try to download the download lasts forever. Can I somehow reinstall google play? What can I do?
Thanks.

Not an answer, but a hint: you might wish to see our google-play-store tag-wiki, which a.o. lists common errors and their solutions. You can also check for other answered questions tagged google-play-store to see if someone else had that issue and was able to solve it.

Go to the apps list in settings, slide to see all apps (including system ones), open Download, clear data and cache of it, reboot and try again. If it doesn't work, try doing the same with Play Store app (you'll need to login again to your Google account).

Thanks. I followed your advice: deleted play and app cache  and was then able to download the kindle app I was trying to download to my device. Thanks.


text:
In the Hangouts app, how do I "mark all as read"?
I'm using Hangouts for texting with my Samsung Galaxy S4. Usually the preview is enough to see the whole message. I hate having to open a message just to mark it a read. Is there a way to mark one, or several, or all messages as read without opening the message?

Unfortunate that this question had never received any love. Despite it being an entire year later, this functionality is not available as a feature in the Hangouts app on Android, iOS, or the web.
Here is the most relevant discussion from the Google Hangouts Product Forum

Thank you for your feedback!
  Yes you are right, there isn't such a button yet. I think Hangouts wants to make sure that you really have read the messages without missing any information.
  However, I'll move your topic to the idea section for the team to consider it as a feature request.
  Nick Ross

This might be more relevant now Hangouts is going away


text:
Setting up Email Notifications based on time & location
I'd ideally like to only receive notifications from an email app (can be the outlook app or the generic android mail app - not gmail or inbox) at certain times of the day or when I'm not connected to our office wifi. This is an exchange account, so using the gmail app isn't an option.
I know this is possible, most likely with Tasker, but I really can't figure it out, to be honest; and have done some searching here and elsewhere on how to do it. If someone could even lightly walk me through it, that would be excellent!

Is there a specific reason why not Gmail? Besides, which Android version and device are you using? Is the device rooted?

There is an app called IFTTT (IfThisThenThat) which I have used before to schedule emails and SMS messages.


text:
How to find and read boot up log files?
My phone's SD card got stolen yesterday, and I'm trying to find a way to read the boot up logs. I had left it at work by accident, and I know that it had to have been stolen by one of our employees in the 8 hour window it was there. Now, I pretty much have my suspicion of who took it, but I need a definite point of evidence I can show my boss before I start asking to check our camera files (pointed outside of the breakroom, not actually one in it to certifiably catch anyone). So, seeing as my phone was on and charging the whole time I left it, that someone would have to take my battery out to take the SD card, and that the phone was already booted up when I came back and picked it up--I figure this is my way to tell exactly who it was by tracking back to that time in the room and seeing who exactly was there.
I can't control what this person does with my SD card or the info on it, but I don't care too much seeing as I have nothing to hide. I'm just really pissed because I had a lot of family pictures and pictures of my late dog on there, and I want to pin the person for stealing my crap, tell them to return my card or get me a new one, and get them out of here.
Also, this is unrelated to the boot files, but I connected my phone to my laptop and it shows some Android data folders were edited at a time when I wasn't with the phone yesterday (com.android.vending and com.google.android.youtube, which has a recently edited cache). I'm guessing this either has to do with an automatic update or someone using my phone...I can't see any files in the folder, only when they were last edited. If there's a way you can help me understand what's going on with this and to differentiate what happened, I would also appreciate it.
Thank you!

If it helps, I have Android 4.0.4 .

Unfortunately for you, the Android log files use a "ring buffer" (think of it as an Ouroboros), so you might not be able to see the startup logs anymore. But here are some things you can do:

Check the "battery monitor" in Settings. Provided you didn't put your device to charge again since, it should show you how long it's been running without being attached to a charger
Using a terminal app or adb shell, run the command uptime – which tells you exactly how long the device has been running since it was last powered up (should also be listed in Settings › About › Status on your device)
different logs can be obtained via logcat, dmesg, and others (see our logging tag-wiki). On ICS (Android 4.0.x), you also can use Logcat & Co..

Keep in mind that every action the device performs "scrolls on" the ring buffer, so older events get flushed out; installing an app will do so, but the other actions as well: screen tapped/swiped etc. are also events. I'd suggest starting with Settings › About › Status if you're after the time your device was robbed of its card.
As for the modified files: At least the Playstore app periodically checks things in background (not sure about the Youtube app here).

Thank you for your detailed response.
Having plugged my phone into my computer, and having removed the battery while I was inspecting the inside of my phone, I pretty much removed the possibility of using the first two suggestions.
I will check into any other logs I can find though.
This is definitely a learning experience for me.
Thank you so much.

Forgot about that, sorry! That removes #3 as well, I'm afraid, as logs are not written to storage (also see: Does android keep a log of when it starts?). // Edit: Only thing I can think about is asking your carrier to check for "drop-outs" – i.e. times in the given "window" where your device cut-off its connection to the network.

Ah, okay. Well, that's also a good suggestion, so I can at least try that.

Good luck with that! To make them more willing to help you, remind them you've got "sensitive information" on that card (which is not a lie, as "personal information" always counts as "sensitive" – at least for "sensitive people").


text:
How to make a 'Captive Portal' on my mobile hotspot?
Some Wi-Fi networks such as those you find in coffee shops, when connected to, automatically redirect you to a web page where you will need to do something (enter credentials, accept terms of service, etc) in order to access the internet.
Is the same possible with an Android hotspot?

I thing it will be posible with new RFC, We just need to add an option to the DHCP handshake, Im looking how to acomplish this either by rooting the device, creating an APP and extend the Wifi-thretening functionallity or changing some DHCP config file for Android 11+ devices follow my work on this here: https://android.stackexchange.com/questions/247548/how-to-run-captive-portal-server-on-android-device-using-hotspot-softap-and-dhcp

Myles Bartlett's answer might be correct in a few respects: This is no simple job! Creating a captive portal on a mobile hotspot would require more than just an app. It would require a backend system to manage user authentication and access control. One possible approach would be to implement a RADIUS server, which is a networking protocol that provides centralized authentication, authorization, and accounting (AAA) management for users who connect to a network.
To create a captive portal, you would need to configure your mobile hotspot to redirect all traffic to a web page that prompts users to authenticate themselves. Once the user enters their credentials, the backend system would use RADIUS to authenticate the user and allow or deny access to the network.
However, implementing a RADIUS server on a mobile device can be complex, and it may require root access. It might be easier to use an existing captive portal solution or consider using enterprise/prosumer wireless access points from a vendor like Ubiquiti Networks, which offers built-in captive portal functionality.

I've made a script that works alongside Irfan Latif's CLI-based AP. I've made some minor modifications to their script, so here's the final result which works in Android 12 (LineageOS 19)(SELinux: Enforcing):
#!/system/bin/sh

# SCRIPT SOURCE: https://android.stackexchange.com/a/215514
# SEE ALSO: https://android.stackexchange.com/a/202335

set -e
#set -x

# this scripts creates a hotspot network

[ "$(id -u)" = 0 ] || { echo 'Not running as root!' >&2; exit 1; }

# Add /vendor/bin/hw to path. That’s where hostapd is in LineageOS 19.0
export PATH=$PATH:/vendor/bin/hw

# check required binaries are on PATH
for bin in iw ip iptables hostapd dnsmasq
do
    ! which $bin >/dev/null || continue
    echo "$bin not found." >&2
    exit 1
done

####################
# define variables #
####################
source /data/data/com.termux/files/home/customAP/config.sh

##########################
# start / stop tethering #
##########################
STOP()
(
    echo 'Cleaning up. Feel free to ignore any errors in this stage..'

    # don't print error messages
    #exec >/dev/null 2>&1

    # hope there are no other instances of same daemons
    pkill -15 hostapd
    # Do not kill wpa_supplicant to avoid WifiSelfRecovery from disabling wifi
    #pkill -15 wpa_supplicant
    pkill -15 dnsmasq
    # remove RPDB rule and iptables rule
    ip rule del lookup main
    iptables -D INPUT -i $AP_INTERFACE -p udp -m udp --dport 67 -j ACCEPT
    # delete AP interface
    #ip link show
    iw dev $AP_INTERFACE del
    #ip link show
    rm -rf $DIR
    echo "Cleanup done."
)

if [ "$1" = stop ]
then
    STOP || true
    exit
elif [ "$1" != start ]
then
    echo 'Usage:' >&2
    printf '\t%s\n' "$(basename "$0") start|stop" >&2
    exit 1
fi

################
# basic checks #
################
if ! iw phy | grep -A10 'Supported interface modes:' | grep -q '\*[ ]*AP'
then
    echo 'AP mode not supported.' >&2
    exit 1
fi

if ! iw dev $WIFI_INTERFACE link | grep -q '^Not connected'
then
    echo 'First disconnect form Wi-Fi.' >&2
    exit 1
fi

##########################
# stop running instances #
##########################
STOP || true

#####################################
# create virtual wireless interface #
#####################################
if ! iw dev $WIFI_INTERFACE interface add $AP_INTERFACE type __ap
then
    echo "Couldn't create AP interface." >&2
    exit 1
fi

#####################################
# configure newly created interface #
#####################################
echo 'Configuring network...'

# activate the interface and add IP
ip link set up dev $AP_INTERFACE
ip addr add ${IP}/24 broadcast ${SUBNET}.255 dev $AP_INTERFACE

# Android doesn't look up into main table by default
ip rule add lookup main

#######################
# access point daemon #
#######################
# create configuration file
mkdir -p "$DIR"
cat <<-EOF >$DIR/hostapd.conf

logger_syslog=1
logger_syslog_level=0

logger_stdout=-1
logger_stdout_level=0

country_code=AR

# network name
ssid=$SSID
# passphrase to use for protected access
wpa_passphrase=$PASSCODE

# network interface to listen on
interface=$AP_INTERFACE
# wi-fi driver
driver=nl80211

# set operation mode, 'g' for 2.4GHz band
hw_mode=g
# WLAN frequency channel to use
channel=9

#Win10 compatibility stuff
ieee8021x=0
eap_server=0
ignore_broadcast_ssid=0

# Security
wpa=2
# key management protocol; use pre-share key
wpa_key_mgmt=WPA-PSK

#Win10 compatibility stuff
wpa_pairwise=TKIP
rsn_pairwise=CCMP

EOF

#Show condiguration
#echo '========================================='
#echo 'Using this hostapd.conf configuration file:'
#cat $DIR/hostapd.conf
#echo '========================================='

echo 'Starting hostapd...'
hostapd -B $DIR/hostapd.conf

################################################
# run a dhcp server to assign IP's dynamically #
################################################
# create configuration file
cat <<-EOF >$DIR/dnsmasq.conf
    # we dont want DNS server, only DHCP
    port=0

    # nameservers to be sent to clients
    dhcp-option=6,1.1.1.1,1.0.0.1

    # range of IPs to make available to wlan devices and when to renew IP
    dhcp-range=$IP,${SUBNET}.254,24h
    # where to save leases
    dhcp-leasefile=$DIR/dnsmasq.leases

    # respond to requests from a different IP broadcast subnet
    dhcp-authoritative
    # don't look for any hosts file and resolv file
    no-hosts
    no-resolv

EOF

# open listening port
iptables -I INPUT -i $AP_INTERFACE -p udp -m udp --dport 67 -j ACCEPT

#echo "dnsmasq config:"
#cat $DIR/dnsmasq.conf

echo 'Starting DHCP server...'
dnsmasq --pid-file -C $DIR/dnsmasq.conf </dev/null

echo "All Done!"

If you're having issues with the AP starting up feel free to uncomment some of my left-over debugging commands.
Also note that most times it takes a couple of minutes (2mins) until Windows 10 actually detects the AP and allows you to connect to it.
For more information about that script, checkout the links at the beginning.
The contents of config.sh:
SSID=MyAP                           # set this to your desired string (avoid spaces and non-ascii characters)
PASSCODE=foobarfoobar               # set this to your desired string (8 to 63 characters)
WIFI_INTERFACE=wlan0                # set this according to your device (check with 'lshw' or 'ip link show')
AP_INTERFACE=${WIFI_INTERFACE}-AP
#AP_INTERFACE=p2p0
DIR=/data/local/tmp/$AP_INTERFACE
SUBNET=192.168.43
IP=${SUBNET}.1

Now, this is the script I made. Run it as root to enable the traffic redirection. Note that running it with "sudo" doesn't work.
# ./captive_portal.sh start

#!/system/bin/sh

source /data/data/com.termux/files/home/customAP/config.sh

# IP the traffic will be redirected to
REDIRECT_IP=192.168.43.1

STOP()(
echo "Stopping dnsmasq..."
pkill -15 dnsmasq

echo "Restoring previous dnsmasq config..."
mv $DIR/dnsmasq.conf.bak $DIR/dnsmasq.conf

echo "Removing phishing redirect iptables rules..."
iptables -t nat -D PREROUTING -i wlan0-AP -p tcp --dport 80 -j REDIRECT --to-port 8080
iptables -t nat -D PREROUTING -i wlan0-AP -p udp --dport 80 -j REDIRECT --to-port 8080
iptables -t nat -D PREROUTING -i wlan0-AP -p tcp -j DNAT --to-destination $REDIRECT_IP

echo "Starting dnsmasq..."
dnsmasq --pid-file -C $DIR/dnsmasq.conf </dev/null

echo "Done."
)

if [ "$1" = "stop" ]
then
    STOP || true
    exit
elif [ "$1" != "start" ]
then
    echo 'Usage:' >&2
    printf '\t%s\n' "$(basename "$0") start|stop" >&2
    exit 1
fi

echo "Stopping dnsmasq..."
pkill -15 dnsmasq

echo "Setting up iptables rules..."
iptables -t nat -A PREROUTING -i wlan0-AP -p tcp --dport 80 -j REDIRECT --to-port 8080
iptables -t nat -A PREROUTING -i wlan0-AP -p udp --dport 80 -j REDIRECT --to-port 8080
iptables -t nat -A PREROUTING -i wlan0-AP -p tcp -j DNAT --to-destination $REDIRECT_IP

# Backup the dnsmasq config
cp $DIR/dnsmasq.conf $DIR/dnsmasq.conf.bak

# Overwrite the config
rm  $DIR/dnsmasq.conf
cat <<-EOF >$DIR/dnsmasq.conf

    # nameservers to be sent to clients
    dhcp-option=6,$IP,$IP

    # range of IPs to make available to wlan devices and when to renew IP
    dhcp-range=$IP,${SUBNET}.254,24h
    # where to save leases
    dhcp-leasefile=$DIR/dnsmasq.leases

    # respond to requests from a different IP broadcast subnet
    dhcp-authoritative
    # don't look for any hosts file and resolv file
    no-hosts
    no-resolv

    # Reply to all queries with my IP
    address=/#/$REDIRECT_IP

EOF

echo "Starting dnsmasq..."
dnsmasq --pid-file -C $DIR/dnsmasq.conf </dev/null

echo "Done."

Then you just start a web server in the IP 192.168.43.1 and you're done!
python -m http.server 8080 --bind 192.168.43.1

Note that this doesn't do any authentication. The script above only does the traffic redirection. You'll have to implement authentication yourself, probably through nginx, PHP and iptables.

You might be able to, if you wrote an app for it.  I'm not sure if the APIs are available though, and whether it would require root or not as I don't develop for Android.  As far as I know, there is no way to do it on stock Android.
EDIT: Android's Native Development Kit could make porting such software easier, however I do not know if one can manage the network in the correct way (the closest most apps can get without root is the VpnService API)
You would need to implement RADIUS or similar.  Trust me, it is complicated even on platforms FreeRADIUS supports.  You might want to just get some enterprise/prosumer wireless access points and use those (Ubiquiti Networks are good ones to look at)

RADIUS is not required for this task.

Most captive portal implementations use RADIUS (at least from my research)

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