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Sim card issues
I have a samsung j1 ace sm-j111m
If I start it without a sim installed it doesn't display the 'no sim' warning
If I start it with a sim installed it doesn't change the top icon for a sim being installed.
I've tried the online guides, ping tests fail and no luck
 I've tried using the sim card info app and it discovers the sim info and voicemail notifications come up
Thoughts? Possible fixes?

Hardware issue probably? Or is this phone locked to a particular network?

I'm beginning to think that but it's not locked as the code screen doesn't come up with any screen so I'm assuming it isn't locked to any network

Sometimes the lock screen doesnt come up. But okay let think it's hardware related then.

I'm not really sure but as the sim card info app reads the card data I don't think it's hardware. I think it has to do with whatever part of the Droid os has to deal with detecting no sim card installed

Can you check if IMEI is still present (*#06#)? I'm starting to think there might be something wrong  with the modem.

Imei and sn still present...I checked already

You should bring it to a repair shop, they should be able to fix that for you.

I've gotten the troubleshooting manual for it and it seems the problem is a fuse ic...can you help me find a replacement?  Google has been less than helpful the code is swv grh66

I don't think you are able to do such technical things. Why don't you bring it to a repair shop?

No one in my country does any board level repairs

No one? Okay. You should ask for help here: http://gsmhosting.com

Have you installed a custom rom? Sometimes custom roms can give this sort of problem. If you are using a custom rom revert back to the stock rom.

I've re flashed 2 different versions of the stock rom and no luck

Was it for your own model? I had the same problem when I flashed an update for devices based on UK and around that region.

Yes correct model but I've no way of telling it's original country so I flashed all the roms for my country and no luck

Did you create a nandroid backup of your original stock rom? If so you can restore your system using it.

No I haven't it's been doing this since I've gotten the phone second hand

Has your problem been solved?

If not what you need to do s search for a proper compatible custom rom for your device and then flash it. Don't use custom roms that have been made for other devices but have specs same to yours.

I have been using stock roms all along


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Mobile VR headsets: hardware or software?

Does the Google Daydream View headset contain any electronic hardware/software components it it? If so, what are their roles?
Same question but for the Samsung Gear VR.
The Gear VR has a label on its side that reads "Powered by Oculus". What does that even mean?

I think it's safe to say the Google Cardboard has no electronic components inside the headset, right? So that's off the list.

Look at the teardown of the two devices:
Gear VR - contains circuitry for the capacitive touchpad on it, plus sensors for detecting if the user is present and USB for connecting it with the phone (presumably to send/receive the above 2 signals).
Daydream View - same for the touchpad, plus NFC chips for one-touch pairing with the phone, and Bluetooth for communication with the Daydream controller.
Gear VR is co-developed with Oculus and thus bears their mark.

source: Stack Exchange

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

sort: votes


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Why can't I move apps from internal storage to SD card on my new Android 7.1.1 device?
Just bought the Moto E4 Plus. Installed a 64gb SD card to hold all my apps so they don't hold most of my 32gb of internal storage. I'm running Android 7.1.1 and I can't move any apps to the SD card. Even ones that I was able to in previous Android versions. Why is this?

It can be because of manufacturer-integrated changes - some manufacturers like to disable Android features of their choice like does Xiaomi in their MIUI, for example.

is there any way to re-enable these features? with or without root?

Maybe enabling adoptable storage will help. Do you have it enabled right now?

no, nor do I know how to check. a lot of Android is new to me as I haven't played with it as much as I'd like to have.

Or you can use app like Folder Mount (utilizes root access) to bind your apps data directories from built-in phone storage to your SD card (only data, not apps themself).

i need a way to move the apps entirely. I'd prefer to have the app backed up as a while instead of just their data.

You can check adoptable storage state and availability by navigating into "Settings" - "Storage & USB" - your SD Card & pressing menu button. If in menu window that appears after "format as internal" option available - then you can format your SD card as adoptable, if "format as external" or something similar available instead - then "adoptable storage" on your phone is already activated and if there is no such options available... Then your phone doesn't support adoptable storage at all. But there is still ways to activate it, if you interested.

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


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What is this "4 white bubbles with a red dot" notification icon?
I see this in my notification bar, but I have no idea what it is

Scrolling down my notification bar doesn't show what it is, and my notification log doesn't show it either.
What is this?

It's Google Assistant. See this

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


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Samsung Tab GT-P5100 stuck in bootloop
PLS HELP MEE!! I was playing with my tab and all of a sudden it started rebooting itself every minute. after that there was this screen asking me to download a custom OS. i don't want to, so i pressed volume down button (it says there to press volume down to cancel. volume up to continue). but i was shocked when it started to download. there was odin which i don't know what it means and says that 'downloading.. do not turn off target!!' so i was too scared to do anything so i just waited for it to finish but sadly it took very very long and i just let the battery drain. when it finally shut down i charged my tab and tried rebooting it. but unfortunately it just stuck in bootloop :(

Seems like you inadvertently booted in Download mode (You held volume down while powering up your device).
You should've just cancelled the process and everything would be fine.
Okay now you are on a bootloop, you can try booting in recovery mode (Holding volume up then briefly pressing on power button).
From there just perform a factory reset and your device should boot normally. Only a con: data loss.

can I still backup my files? especially apps like my games data?

also I went to recovery mode and there were 'apply update' either thru adb, external drive, or cache. should I try looking for an update?

I don't think you can have a backup. Those apps can be found in Google play store though. Applying an update may solve the issue, but I'm not sure.


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ADB can detect devices but it can't detect device in recovery move
I am using mac.
I am trying to install twrp on my Galaxy Note 8.0 GT-Nn5120, via adb. ADB can detect the device when in normal mode but when i boot into recovery mode, it can't detect the device.. What do I do

Are you using the stock recovery? It's possible that you have to use another recovery such as TWRP to use ADB in recovery. From my experience you need to install the recovery using ODIN.

I'm using stock recovery, I want to flash TWRP but I'm using mac so I can't use odin, how can I do this?

You can't ADB in recovery mode, not with a stock recovery. You can only ADB Sideload which is used to flash zip packages (updates, gapps, etc). To install TWRP, you need to flash it in Download mode.

Download TRWP or here
Boot in Download mode (Hold volume down then briefly press the power button. Press Volume up to confirm).
Download and unzip Odin then launch it.
Click on PDA or AP button and select TWRP file you downloaded previously (Should be in .tar format. If in zip, unzip it)
Click on Start button
When you see PASS, disconnect the phone and power on (Hold volume up this time: you should boot in TWRP recovery )

As a side note, a stock recovery doesn't allow sideloading flashable zips that are signed by anyone other than the manufacturer.

how do i use odin if I am on mac?

On Mac you'll need Heimdall. It's the Mac equivalent of Odin (Windows). @L.Tommy

lol can't install heimdall because "not compatible with this version of OS". I give up, i'll just settle for nova launcher and icon packs

Oh, sorry to hear that


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How do I disable Google Chrome from using regional google search?
I am using a VPN app
 and I don't want google to give me Arabic searches if my VPN is Arabic (besides, the whole site is mirror-imaged, since Arabic is written backwards). I want every search on Google to go to either google.com or google.co.in. I have tried searching, but all of them are about Chrome in PCs, and not for Android.

Installed the VPN app and checked
Easiest way is to choose an English speaking location like USA instead of app choosing the location in auto mode
Alternatively, use other search engines available under Chrome settings → search engine. It appears Chrome picks up default search engine based on location, which happened to be Arabic based on the choice of VPN

You can visit these addresses below everytime you want to do a search or simply bookmark it. There is no way to add a custom search engine on the mobile Chrome version.
Google Search No country redirect or www.google.com/ncr
And now when you search with Google Chrome, it will always search using Google.com in English without the country redirect.

"There is no way to add a custom search engine on the mobile Chrome version." Big bummer. Is it possible to "pin" my country settings and forbid Chrome from changing country redirect?

i don't think that is possible.


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Is it possible to hack android phone by contacting the target over Gmail or Skype, if the target does not downloads suspicious files sent over?
In other words, how safe is having Gmail or Skype conversations with complete strangers on android? Suppose the target is wise enough to not open any suspicious files sent to him. How else could his phone be hacked?
I have heard that it is possible to know the ip address of the sender on Skype. But a cyber criminal knowing your ip address is the same as a burglar knowing your address. The information is necessary but not immediately sufficient.
Also, which, between Skype and Gmail is safer for the user in these cases? I guess Gmail is safer, but don't know why and by what amount. Also, how exactly does the danger increas for users using old version of the android- like 5.1 or 4.4.2, let's say? I guess the older the version, more the risks.
Sorry for sounding paranoid, but one is afraid of things one does not understands, they say. Thanks for helping...

You might wanna check with [security.se] (but please do not repost). They have a user base more inclined toward issues on information security.

Android Apps are sandboxed. If someone can "hack" skype, they may be able to get data from the skype app, possibly including contact list, login credentials and chatlogs. Further they may get everything, what the skype app can access, which probably includes the phone's address book as well.
If your phone has a remotely accessible flaw, which would be a reason for the fear that somebody could get your ip address, you have bigger problems than your skype contacts and should upgrade your android ASAP. Further, modern skype isn't peer to peer anymore but a skype server is used. Finally your phone will be most the time firewalled in your LAN or in cellular networks because of CGNAT. Which may be false security, i.e. if somebody is in the same WLAN like you.
I am not aware of any remote security flaws in android, but there are many local ones in older android versions, including ones triggered by special image files (which could be sent via skype) and similiar attack vectors.


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applying updates to no name Androids (Homtom HT20 in this case)
I have barely managed to get into the recovery environment. The phone has everything stock.
The attempt to adb sideload [update_file].zip has failed with a timeout exception. The device has developer options enabled I a am able to freely use adb on it (in normal mode, not recovery)
The attmept to apply the update file from SD card also fails like this: I first click to apply update from SD card, select the file, then I get the resting robot with "No command." text. If I leave it like this, it will stay here for afew minutes then reboot all by itself - checked the ROM version and it looks like still the old one. If I try to get exit this screen with "power" + "vol up" it goes into a menu screen made out of "reboot now" or "continue with the update" - none of which are of any help.
Any chance for this pretty broken phone to get its update ?

Update file corrupted ? Check the MD5 signature or download again

Based on @beeshyams comment i have dug deeper only to find out that the Chinese phones have their own way of updating the ROM. Namely through the "Sp Flash Tool". More on the process at http://4pda.ru/forum/index.php?showtopic=469340 (in English - https://translate.google.ro/translate?hl=ro&sl=ru&tl=en&u=http%3A%2F%2F4pda.ru%2Fforum%2Findex.php%3Fshowtopic%3D469340)
I might try to root it as well depending on how much of a fix this update made for my flaky internet connection problem.


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How to stop a Samsung Galaxy Note 10.1 (2014) from booting into recovery?
My Tablet is stuck in booting into a (not working) TWRP recovery. It shortly shows the Bootloader screen with "recovery booting ...", then the screen turns black and it reboots.
The LineageOS itself was booting fine. I tried all kinds of button combinitions to cancel recovery booting and get the system to boot, but it keeps booting into the broken recovery.
Is there any kind of hotkey to get the phone into a "boot to system" mode again?


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Why is Outlook for Android using a weird From address?
My wife uses Outlook.com for her email and has an alias assigned from a domain we own.  The alias is the default address. Works great while she is using Outlook.com.
She also uses Outlook for Android (OFA) on the Samsung Galaxy Edge 7. She's signed into the same account, but when she goes to compose an email, the From shows as an odd outlook_398f6...@outlook.com address instead of her alias.
In the drop down of aliases in OFA, her normal outlook.com address appears along with the weird one, but the alias from our domain is not displayed.
Last odd fact is in the OFA account settings, the Account Name is actually listed as our domain alias account.
What I've done.

Swapped the default aliases a couple times on Outlook.com
Reset the account in OFA
Removed and added the account on OFA
Uninstalled and reinstalled OFA

Does this "weird" address also appear on Outlook.com? Have you tried sending an email to your other personal account and checked the From field? My current wild a** guess is that Outlook for Android doesn't support custom domain and that "weird" address is actually the same alias on Outlook.com

On the second thought, are you asking only about the weird From address, or also if an alias is supported on Outlook for Android? Because the answer to the latter seems to be: no, it's not supported (AndroidCentral forum, official feature request), though it seems someone did succeed. (AndroidForums)

I assume the address is an internal alias to the custom domain address.

I guess the question is whether it is supported.  I'm pretty certain it has worked for her in the past, but reviewing the item to referenced, it appears that it does not work now.


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Activating VoLTE in Moto X Force
I had recently had a hand on my friend's Moto X Force 1580. The phone works on Android 7.0. I went through the web and found out some guys claiming to make Moto X Style to work on VoLTE. I followed the same procedure but had no luck. Following is the procedure that I went through.

Dial *#*#4636#*#*
A hidden menu would start, select "Phone Information"
In this window, there is a switch that says "VoLTE provisioned". This by default is off, turn this on
Restart the phone.

I tried this number of times, but it turns back off every time.
Can anyone help?

Basically what you want is to keep your phone in 4G LTE while making/receiving a call, but it is dropping to 3G/2G, right?
I have worked in 2 big Android phone manufacturers on Software teams. And both had the same policy. It's too risky to enable any feature on an Smartphone without tests.
And VoLTE/VoWifi/ViLTE and now VoNR (5G) are all enabled/disabled carrier by carrier. One of the reasons your phone has VoLTE disabled for you carrier could be:

You bought the phone in a different country than where you are using it.
When you bough the phone, you carrier didn't support VoLTE at the time. And the cost to test and enable it now is too high for a phone that is not been sold anymore.

So you could try to put a SIM card of a different carrier to see if VoLTE is enabled. Try the biggest carriers of your country.
There is a service named "carrier_config" that handles all IMS enablement. You can type:
$ adb shell
$ dumpsys carrier_config | carrier_volte_available_bool

To confirm the parameter. You'll probably get:
carrier_volte_available_bool = false
But unfortunately I don't know how to set it to true using ADB. I only know changing the source code.

Your phone doesn't support VoLTE

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


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Xiaomi Redmi Note 4: unable to acquire unlocking bootloader permission
I've created a MIUI account through my Redmi Note 4 and applied for permission to unlock the bootloader through the official Xiaomi unlocking link.
The problem is that after I enter my phone number so that they send me the code which I'd use to apply for the permission --which takes a lot of time to receive but I was patient and waited-- it gives me a pop-up message in Chinese in which it's roughly translated to: "You have reached the limit for this IP".
Please keep in mind that I haven't signed up with many accounts from the same PC. I've tried another email, phone number, and a new MIUI account from a totally different PC and it still gave me the same pop-up message.
I really want to root my device. Please help!

"another email, phone number and a new MIUI account from a totally different PC" but still under the same network? Won't help when it's saying "reached the limit for this IP"... Probably want to try doing this from elsewhere.

By "same network" you mean same internet provider? or same mobile network provider? coz if it's the latter then no, i've used another number with different network (aka different mobile network).

That's weird indeed. At this moment I'd consult people at MIUI forum for help...

It is a known fact that ISPs are allocated a bunch of IP addresses which are then dynamically distributed among the public. So, every time you connect to the internet, it is possible you are allocated a different IP address, and sometimes it might be the same (try whatismyip on your browser to see your IP address). So, try the procedure using mobile data.
If it still doesn't work, I would like to suggest to you an unofficial method mentioned in XDA and I request you to go through the entire thread.


text:
Flash Soft Bricked Locked Nexus 6P
How can I get my soft bricked Nexus 6P working again?
I don't mind flashing it, losing all data etc. I'd rather have it done now than send it away to be fixed.
It's caught in a boot loop where it only makes it to the white Google logo, then restarts. I can get to the bootloader and occasionally I can get to stock recovery mode.
Running adb oem device-info returns:
(bootloader)    Device tampered: false
(bootloader)    Device unlocked: false
(bootloader)    Charger screen enabled: false
(bootloader)    Display panel:
OKAY [  0.058s]
finished. total time: 0.058s

Running fastboot flashing unlock returns:
...
FAILED (remote: oem unlock is not allowed)
finished. total time: 0.021s

What is my next step here? Any help is appreciated.

In case anyone else has a similar problem, I send the phone away to get repaired and the problem was that the power button was stuck, causing the phone to turn off.

I think your bootloader is locked you need to get the unlock key from the manufacturer website i have done it on sony phones to look at an example visit the sony developer site and read as much as you can to understand better what is going on


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Unlock the SMS Limit on Android Marshmallow
On Android, there's an SMS Limit that prevents a new message from being sent after a certain amount of messages have been sent in a certain period. Due to a personal need, I need to send more than the limit by unlocking it.
I already tried downloading apps from the Play Store that unlock SMS but no luck, although I completed the required prerequisites, seems like it's not working on Marshmallow. I also tried using ADB command, but the Settings.db was not found in provider settings.
How to unlock the SMS limit on Android Marshmallow?

Are you sure the limit is Android imposed rather than carrier-imposed?  I've never heard of an SMS limit on Android.

This may fix (not tried by me ) - https://www.xda-developers.com/increase-the-sms-limit-on-android/

This method work on a non-rooted phone, I use it on Android 7/8:

On the phone, install Settings Database Editor and open it
On the PC, install the driver for your phone, then connect to the phone using a USB cable
Download this zip file containing a folder with minimal ADB and extract it to a folder
Open a command prompt and browse to the extracted directory
Type adb devices to check if the phone has been detected by the PC. If the status is "unauthorized", a pop-up should appear on the phone, accept it to allow ADB to communicate with it
Type
adb shell pm grant by4a.setedit22 android.permission.WRITE_SECURE_SETTINGS

to allow the app to overwrite Android settings
Restart the phone
Open the app and add a new setting in these categories: system, secure, global. Push "+Add new settings" button on the top, then input sms_outgoing_check_max_count with value 99999
Restart the phone

And now you can send a lot of messages.


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Unfortunately, Google Play services has stopped?
I recently bough an Android computer from China. However, it does not have Google Play Store on it. I've tried downloading and installing the Google Play APK. The installation appears to be successful, but it freezes each time that I try to open it, with a message saying "Unfortunately, Google Play services has stopped" The system has Android Version 6.0.1 and Kernel version 3.10.0.

Naturally, you cannot simply install Playstore as user app. First, it needs to be a system app, and second it depends on several other Google apps (GSF, Google Services Framework – see Wikipedia). For details, please check with our google-play-store tag-wiki and especially follow up to How can I install the Google Apps Package (Play Store, …) on my Android device?
Alternatively, you could e.g. use the the YalpStore app (and optionally the microG framework, an open-source GSF alternative – not really needed by YalpStore but would provide the needed services for other apps usually depending on GSF).

I have downloaded Yalp Store successfully. It seems to be working, but I'm unable to log in into one of the software I downloaded.
Do you know what this means...
"Not allowed to start service intent [act=com.google.android.c2dm.intent.REGISTER
pkg=com.google.android.gms(has extras)] without permission
com.google.android.c2dm.permission.RECEIVE"
I get this when I try to log in into a Point Of Sale software I downloaded through your Yalp Store.
I'll appreciate your insight.

That app obviously requires GCM (Google Cloud Messaging), which is only available via Google Apps or microG. See second paragraph of my answer and follow the link.


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How can I prevent certain websites from appearing in my Google search results?
I'm looking for a method to stop a given list of websites from appearing in my Google search results. Any chance I can achieve this?

For Android phones, You have to just click on the options button at the top right corner of the website you want to block and then select not interested in stories from xyz.com. Google will now stop showing anything from that website to you.
If you are using the Chrome Browser on PC, then you are lucky. Because, Chrome has an official extension called Personal Blocklist just for this. You can download and install it from here.

Umm, we need a solution for Android. Chrome extensions are good but Chrome for Android still doesn't support them.

Yea. But I think you can block a particular website in Android from your Google Now feed and Google news website. Not sure about the search results though.

That may be true. Could you please provide details on how to do that with Google Now Feed? That may very well help others too.

Yea sure. You have to just click on the options button at the top right corner of the website you want to block and then select not interested in stories from xyz.com. Google will now stop showing anything from that website to you.

@RajaSekar Please edit your answer and put your previous comment as answer if you feel it answers the question. The original answer is for Chrome for PCs, and I don't think it's relevant here :)


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When activating DATA, all Apps wants to go online at the same time. any fix?
I like to deactivate my 4G Data or Wifi when I'm not using it.
But whenever I activate Data (4G or Wifi), all the Cores of the CPU are being used at 100% and the phone becomes unusable for at least 30sec.
So it seems that All the APPS wants to go online at the same time, rather than one by one.
It's very annoying when I just want to go online for the GPS or the Browser : I have to wait 30sec minimum every time.
[Phone : Samsung S3 I9300 with Cyanogenmod]

Maybe Greenify?

How many apps do you have? Which CyanogenMod version are we talking about? What app are you using to see info concerning the CPU?

micro CPU monitor. CyanogenMod 11 (4.4.4), 34 apps. I block half of them via a firewall (droidwall) but even with or without it, I have the same issue.


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Android Smart Lock: Why is there no option to use WiFi?
My Android device (v. 7.1.2) offers several options to use the "Smart Lock" feature.
This feature uses some rules to automatically disable the lockscreen.
Available rules are:

Trusted place
Trusted Bluetooth device
Trusted face
Trusted voice
On-body detection

I am surprised that there is no option to use a trusted WiFi network.
Some forums state the risk for the WiFi network to be spoofed. I don't understand how the risk is different: an attacker could spoof a Bluetooth device as well.
What could be reasons for not allowing a WiFi-based unlocking while allowing Bluetooth-based unlocking?

I honestly believe this question can be answered along technical lines without the need of introducing opinion. I request close voters to please let us know why do you disagree?

@Firelord wasn't me, but "why" questions tend to be opinion-based. We can come up with reasons why *we" would do X – but unless there's an official statement from those devs, we never know. Further, it rises the question: "What problem shall be solved here?" ;) // Not saying it must be closed, just trying to shed some "opinion based light" on possible reasons of voters :)

Some forums state the risk for the WiFi network to be spoofed. I don't understand how the risk is different: an attacker could spoof a Bluetooth device as well.

The risk is different. It's not possible to spoof a paired Bluetooth device. The Bluetooth peripheral and the phone exchange keys as part of the pairing process, so both of them can securely identify the other. When the devices connect, they each challenge the other to prove they have the secret keys. If it didn't work this way, it would be trivial to "man-in-the-middle" attack the connection by pretending to be the peripheral. Then the attacker could eavesdrop your phone calls or music, or whatever it is you're sending over Bluetooth.
Authentication works a bit differently in Wi-Fi. See this question on our sister site Super User for more discussion on that. In open networks, and networks authenticated using WEP, WPA, or WPA2-PSK, the network doesn't authenticate to the phone at all. The phone has to prove that it has the secret key (the network password), but the network doesn't have to prove anything. There are no "trusted Wi-Fi networks" in this sense. Only networks authenticated with WPA2-Enterprise, which use a certificate pair, prove their identity to the phone, by showing a certificate signed by a certificate authority (just like HTTPS websites). Presumably, Google didn't think it was worth adding an option that would only work with the least common type of Wi-Fi network, and the confusion it would cause their users.
Interestingly, Wi-Fi spoofing is already a security issue for the "trusted place" option. The location system uses visible Wi-Fi networks as one input to determine where you are, and as we've seen, that can cause huge inaccuracies. Spoofing this deliberately means looking at the networks that are visible in your "trusted place" and spoofing several at once. Your neighbourhood phone-snatcher won't be able to unlock your phone this way, but government agencies and organised industrial spies probably can: especially if they also use a screened room to block GPS and cellular signals.

You can also spend $100 and get a Pineapple and now you can unlock everyone's phone who was stupid enough to use an insecure method for smart lock. Or you know, just don't enable insecure options.

@WayneWerner Pineapple?

@Revetahw https://www.wifipineapple.com/

Note that even most WPA-Enterprise networks don't actually use certificates. All the ones I've ever seen do RADIUS over something like EAP.

@MikeOunsworth Thanks for pointing that out. I started out searching for such a question on security, and then failed to notice I'd followed a link to SU.

WPA-enterprise with certificates is quite common in UK universities.  If Google built this in, would you really want your phone to be unlocked whenever and wherever it is on campus? (Or in your office building for that matter)

Unfortunately, this answer is wrong. In WPA2-PSK, both the station and the AP have to prove that they know the passphrase in the four-way handshake. AFAIR, this should also be valid for WPA and even WEP, but they have other vulnerabilities. For WPA2, security is only compromised for inside attackers (Hole 196 attack) or when the PSK is easily guessed, brute-forced (using encrypted Wi-Fi packets) or leaked.

@Dubu I'm not a huge expert on Wi-Fi security, I just went on the accepted answer to this question

@DanHulme Thank you for the heads up, I just commented on that answer too.

While it might be possible, one would have to know the name of the SSID, and have serious knowledge about how doing such attack. In the meantime, 4 digits password or dumb pattern recognition are valid method to unlock a device...

@ChristopheVidal The attack is really simple to do if you know the SSID of a "trusted" network, and most networks broadcast their SSID, so you can get some likely SSIDs to unlock the phone just by looking up the victim's home or office on openwifimaps.

What you ask would certainly be possible, but it should be restricted to when a device is connected to a Wi-Fi network using sufficient security, i.e. WPA2 authentication/encryption. Probably it was left out because it would be hard to communicate to a non-technical user why they could use certain Wi-Fi networks for authentication but not others.
In contrast to what @DanHulme wrote in his answer, when using WPA2 authentication with pre-shared keys (WPA2-PSK), both the station and the AP have to prove that they know the passphrase in the four-way handshake. A rogue WPA2-AP cannot give access to a client by just "accepting" the client's password. On the other hand, everyone who knows the PSK could fake an AP (WPA2 Enterprise does have an advantage here over WPA2-PSK).

+1. Now this makes sense An often requested, but not particularly secure (unless using a WPA2 profile that authenticates WiFi access points),


text:
Unable to get bluestack downloaded data
I installed Bluestacks and  I am trying to access files downloaded via Bluestacks but I seem not to find these files (folder is empty). I have also installed ES file explorer . Can anyone provide a  good solution on how to access these files ?

You mean download folder?

You might also wish to see How to transfer files between BlueStacks and Windows PC for related answers.

My path to shared data is
C:\ProgramData\BlueStacks\Engine\UserData\SharedFolder

+1 Thanks a lot for the update! It is indeed the path for newer versions of windows specifically Win 10. In older versions it was just C:\ProgramData\BlueStacks\UserData\SharedFolder

There is a nice tutorial explaining how to do this:
As Bluestacks emulates Android, the default download path should be similar i.e. /sdcard/Download (or /storage/sdcard/Download)
Using a file explorer e.g ES explorer, browse the file structure until you come across the root folder, from there try locating the above path.
Now Bluestacks has an integrated Shared folder with Windows in the following paths:
/storage/sdcard/windows/bstsharedfolder/
or
/sdcard/windows/bstsharedfolder
In order to access your downloaded files in Windows explorer, you need to copy the contents of the download folder (/sdcard/Download) to the Bluestacks Shared folder (/sdcard/windows/bstsharedfolder) using ES file explorer.
Finally access the downloaded files from the PC via Windows explorer from this path:
C:\ProgramData\BlueStacks\UserData\SharedFolder
Remember to enable the option "Show hidden files and folders" in Windows explorer options
Update
If you are unable to find bstfolder in its default Windows location [C:\ ProgramData\ BlueStacks\ UserData\ SharedFolder ], you can find their actual location from the Windows Registry.

Access the Windows Registry by going to Start >> Run and type in “regedit” and hit Enter. This opens up the Registry Editor.
Go to HKEY_LOCAL_MACHINE\SOFTWARE\BlueStacks\Guests\Android\SharedFolder. Each of the numeric folders represents a shared folder, and their location is indicated in their Path String values.

You may have to manually set the Bluestacks shared folder in the following way:

go to HKEY_LOCAL_MACHINE\SOFTWARE\BlueStacks\Guests\Android\SharedFolder.
Create a new key here and rename it to the number following the previous key.
Inside the newly created key, right-click on the space on the right side and create a new String called “Name” by selecting New >> String.
  Double-click on it and enter a value.
The value is the name of the folder as seen inside BlueStacks, additionally create a new DWORD Value by right-clicking on the blank
  space and selecting New >> DWORD (32 Bit) Value and rename it as
  Writable. Right-click on this newly created value and click Modify.
  Set the Value data field as 1 and select the base as Hexadecimal.
Create another String called “Path” and assign a value of the full path of the directory you want to include inside BlueStacks.
Restart your computer for the changes to take effect.

Now you will be able to access BlueStacks files from Windows.

Update:
As mentioned by Josh Davis if you can't find the path in newer Windows version, navigated to this path instead: C:\ProgramData\BlueStacks\Engine\UserData\SharedFolder

still shared folder empty

Please edit your question with clarification on what you're trying to achieve, right now its hard to guess what's happening, and also the above workaround is one of the most probable solution

my issue is that..whatever i download from bluestack i am not able to find it in my computer...

can you help me thorough this

Not that this is a help...but I have a co-worker that has the same problem since using Bluestacks 3. (Maybe it would be a plan to go back to Bluestacks 2 because of this...)

@Yosroel Agreed! perhaps this is the only way out

I think your question is

"You are not able to find your downloaded files which you have
  downloaded over bluestacks"

You can move to this ----
C:\ProgramData\Bluestacks\UserData\SharedFolder
here you will find all your shared data

First enable hidden files and folder to view program data folder

or you can  just send all files to desktop from bluestacks to view all your files and other stuff
hope this will help you...

i already checked this folder so many times..but it shows empty..

you can also install es explorer and choose send to windows this will help you

how to do that can you tell steps? i already installed es explorer

Use the Media Manager to transfer files from Bluestacks to Windows.
Here are the steps.

Click on My Apps tab.
Click on System app.
Click the Media Manager.
Long left mouse click on the file you want to transfer to Windows.
At the top click on Export to Windows.
Select a location in Windows and your file will be saved there.
In Windows browse to your save location and now you will have the file located there.

My path as of 9/6/2018 in Windows 10 is:
C:\ProgramData\BlueStacks_bgp_kk\Engine\UserData\SharedFolder
ProgramData is a hidden file in windows 10.
In ES File Explorer I go to:
Home->Internal Storage->Windows->BstSharedFolder

Here are the same files in Windows File Explorer:

Note the path.
I have BlueStacks 3 installed.


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Supersu complains about needed update
I have successfully installed TWRP 3.1.1 on my HTC Desire 510. I have rooted the phone with a modified ROM (so I think).
But supersu keeps complaining: "Die SU-Binary muss aktualisiert werden. Fortfahren?" (i.e. super-su binary must be updated. continue?)
If I continue, I can choose between "normal" installation and "using TWRP/CWM" for installation. Neither works.

"Normal installation" yields "SU update unsuccessful" and leaves me a reboot or a link to some tutorials.
"Installation using TWRM TWRP manages to boot directly into TWRM TWRP (yeah!), but does not change anything. super-SU comes up with the same message after reboot.
I also downloaded the last super-SU zip and installed it from TWRM TWRP, but with the same outcome.

I have some suspicions.

the phone might not be rooted properly? I unlocked its bootloader according to the HTC standard process (fastboot and token generation on HTC's website). This at least allowed me to install TWRM TWRP and a modified ROM. I checked root access with two different root checkers and they told me, my phone was properly rooted
supersu is somehow broken?

Sorry that was a typo. I corrected it transparently. TWRP makes more sense, doesn't it? I'll look up the supersu version I used later, as I can't look it up now, but I downloaded it last friday, and I think it was supposed to be the latest.

How do I identify v2.79 version 3? I found "SuperSU-v2.79-201612051815" for download. Is that the right version?

Ok, downloaded it, installed via TWRP, but the superSU app keeps complanining, that I "must" update the binary. Perhaps I just should ignore that?

Let us continue this discussion in chat.


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Can I use a windows 10 computer with Bluetooth as a trusted device for Smart Lock?
I have a desktop computer with an old Bluetooth 2.0 dongle and a HP laptop with Bluetooth 4.0 that I can pair successfully to my LG G3 running stock Android 5.0, but when Secure Lock asks me if I want to add that device as a Trusted Device, it fails and it tells me that I can't use that device.
Can a Windows machine be used as a trusted device at all or do I have to change some setting?

I recall vaguely that it works if you pair the device when it is active -like sending a file or something and while it is doing this you can make it a trusted device. That's what I remember -source ?.. see if that helps

There is some evidence suggesting it can be done, however only devices that are currently connected and in range can be enabled,  so make sure you're connected to the device you want to use i.e Windows 10

Device-to-device e.g tablet, PC (as opposed to device-to-peripheral e.g smartwatch ) connections only remain established during the time of need such as data transfer.

Some users have suggested using Bluetooth services on PC, to keep constant connection. Examples include Bluetooth audio service, or  connecting the PC an input device (remote control), Obex or even DUN so as to prevent connection  drop.
Credits
Trusted devices not staying connected


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Android Revolution HD on GT-N8010 wifi won't turn on
I just flashed the Android Revolution HD rom on my Samsung Galaxy Note 10.1 (GT-N8010). My device was in 4.1.2 and now is on 4.4.2. I seem to have one big problem: After pressing the wifi toggle slider it looks as if it would turn on but immediately goes back to off.
I've checked that the rom I used is the right one. So, what would be the cause of this? And more importantly, how could I solve it?
Thanks in advance!
Schlotty.
Link to the ROM thread: https://forum.xda-developers.com/showthread.php?t=2119547

Tried other ROMs? Also, since ARHD is a stock-based ROM, it's possible you'll need to be on the latest stock ROM before flashing it, so as to make sure the baseband, etc. are up-to-date.

Yep, after trying with a couple of roms and a little reaserch I came to the conclusion that i would first need to be on 4.4.2 in order to flash ARHD. Problem is, my carrier hasnt recieved a kit kat ota update, so... The only thing that seems reasonable is to first flash a stock KK rom from a different carrier and then flash ARHD. Does that make sense? Would it be possible to flash a stock rom from a different carrier on my device?

Since ARHD is a stock-based ROM, it's possible you'll need to be on the latest stock ROM before flashing it, so as to make sure the baseband, etc. are up-to-date.
In case your carrier doesn't offer a 4.4.2 update, find them on SamMobile and download one for your generic region, or another carrier in the region, so as to get the right set of language (not all languages are available in all firmwares). Making sure the model number matches is the only other thing you need to do. Back up your data, then flash the update with Odin. After booting up the new stock OS, flash the recovery and then ARHD once again.


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how to recuperate data from Nexus 5 with broken screen and USB debugging off?
So I was exercising hard and my phone fell ackwardly from the elliptic, the phone died, when I picked it up, my screen was full of lines. The glass does not seem broken but what is under the glass seems broken.
The screen shows full of crazy lines, they move a little, it seems to be a spaced out version of what the phone would normally show.
So in the screen I cannot see much, also I cannot seem to interact with the screen anymore, I suspect that the screen is also sending many random touch signals make the phone go crazy and make old modem noises when booting it normally.
So my hope is to simply connect this phone to my Ubuntu with adb so I can regain control and get my files.
So far I have discovered the following.
I can turn off the phone by holding the power button a long time.
After that I am able to boot it in a way that fastboot can see it and control it by holding either volume down + power or both volume up and down + power and releasing as soon as *something appears on the screen.
From there I can mess around with fast boot.
at first I had:
sudo fastboot oem device-info
...
(bootloader)    Device tampered: true
(bootloader)    Device unlocked: false
(bootloader)    off-mode-charge: true
OKAY [  0.003s]
finished. total time: 0.003s
And I was not able to flash twrp recovery
I was supposed to be able to unlock it with fastboot oem unlock but I was just hanging at waiting for device :( however I understood that after the oem unlock there is a comfirmation on the phone. I had to use the volume keys and go down a few times and press power, it was a pretty blind not easy operation really but it actually worked!
So now I get:
sudo fastboot oem device-info
...
(bootloader)    Device tampered: true
(bootloader)    Device unlocked: true
(bootloader)    off-mode-charge: true
OKAY [  0.003s]
finished. total time: 0.003s
(houray)
and I was able to flash twrp on my recovery partition with
fastboot flash recovery twrp-3.1.1-0-hammerhead.img
(this is supposedly the correct version of twrp for my Nexus 5)
target reported max download size of 1073741824 bytes
sending 'recovery' (14604 KB)...
OKAY [  0.674s]
writing 'recovery'...
OKAY [  1.153s]
finished. total time: 1.828s
bang!! seems to work, I can flash paritions there should be a way to salvage my file!!
and thats how far I have gotten. Now when the phone boots the crazy lines/colors seem to be different but I cannot seem to go any further. Still when I type
sudo adb devices
I get nothing.
Can anyone help me out on this?
Is it possible that twrp boots but wont work properly since my phone sends plenty of touch signals through its broken screen? Can I use the physical buttons to do enable adb in twrp?
I should now just have to do
fastboot reboot
(possibly holding certain buttons, I pretty much tried them all)
and twrp should boot and I should be able to see my phone with adb. but I dont...
sudo killall adb
~/Desktop$ sudo adb devices
* daemon not running. starting it now on port 5037 *
* daemon started successfully *
List of devices attached
does anyone have any insight as to how can I get this phone connected to adb.
I think twrp is booting but its hard to tell with that crazy screen. Is there something I need to do with the physical buttons?
well Im not sure if I should post this anymore because I just found my answer it seems. For the good of humanity and others in need I will post it and the baby Jesus shall decide what happens with it.
So I was finally able to get in adb!
It was all about that step where it said you need to hold some buttons when you boot. Well I was holding just volume buttons, turns out I had to hold power too (for some reason I though since it was already rebooting only the volume keys would send the necessary signal)
so I reflashed twrp with fastboot, held basically all the keys (vol up and down + power) and did fastboot reboot. Then suddenly it booted and right away my Nexus drive appeared on my computer, accessible. I was like holy hell lets get my files now!! But I couldnt see them I was in what seemed to be a blank phone with empty Download, Music etc folders....
Turns out all my files were gone. Doing adb shell I could linux into the phone and a df -h showed my main partition 12G was only 6%, thats uncharacteristic, my phone was always so full!!
It appeared that at some point I wiped the phone. Im not sure actually but I suspect it might have been when I did fastboot oem unlock, doesnt that wipe your phone for security? Either that or I accidentally picked the factory reset while trying to navigate in the bootloader without seeing anything.
Oh well I didnt have much on there anymore. Only lost about 2 weeks of Exiled Kingdoms gameplay and will need to redownload a few books/songs...
Although I found my answer, Im going to post this in case it can help someone.
Cheers!
(note I had to yank out all the links to other articles that were helpful because stack exchange says my post looks like spam..)
=========EDIT
I was wrong about 1 thing. I dont need to hold the power button the procedure to be able to connect adb on my phone with broken screen (cant see except vague colors, cant touch) and usb debugging disabled, here is the exact procedure now that I have done it a few times:
(note that I first had to unlock the bootloader, how is explained above)
-power off holding power button longtime (USB must be disconnected for some reason) until it stops throwing random vibrations
-boot holding vol down and power, release at first thing poping on screen, then youre in fastboot
-sudo fastboot devices (you should see a device)
-sudo fastboot flash recovery twrp-[correctversionforyourphone].img
-then hold power down and type in sudo fastboot reboot
-release at first thing on screen
-then you get in a screen where you need to select recovery, this video helped me see what the menu looks like: https://www.youtube.com/watch?v=ku3xF8gh22M basically there are 4 options and the 4th is recovery so I guess you could just press vol down 3 times and then press power to boot in recovery (but my phone still shows crazy lines and while it doesn show much its enough to see that 1 option is white, 1 is green and the 2 others are red, I want the second red option, see the video...)
-when you have navigated to the recovery (4th option) press power to select and hold the vol down button right after (so the phone wont override recovery flashed??)
at this point I see the phone drive pop up on my computer and I can also use adb on the phone. Of course it is wiped because I had to unlock the bootloader earlier.
Now Im thinking there is maybe 1 crazy way to get my files back. The Google Android backups! My new phone now is a LG and so I cant get the normal android backups on it but I want to try the 2 next things: use adb to screecast my broken phone on the computer and restore android backup?? use an emulator, put in my Google account and restore android backup. Maybe this can allow me to restore my lost files. It is weird that I can see my android backup in my google drive but there is no option to download it :(
=========EDIT 2
In the end my last idea did not work either. I was able to get a nexus 5 running in the genymotion emulator and add my google account to it. From there I could enable the backups but I could not find a way to restore a backup from my old phone anyways it seems that these android backups only contain app backups and settings backups. Im not sure it would contain the books I was accumulating in the Books folder or save games from Exiled Kingdoms. I guess I'm now giving up at this point.
It seems to me that if you lose your screen on your phone and
-USB debugging is off
-you have a PIN and home encrypted with the PIN
-your bootloader is locked
There is no way you can recuperate your stuff from the device. Correct me if I'm wrong. Maybe I could have tried to talk to the phone "hello Google" and do something but I dont think I could because 1: it wasnt setup and 2: the cracked screen made the phone go crazy when booting normally.
Time to move on!

Correct, unlocking the bootloader wipes the /data partition.

Could you please post the question as a question and its answer as an answer below? Your effort to help fellow users is appreciated but please understand that this site conforms only to Q&A style, which means no forum like posts.

Apart from what @Firelord said, you might also want to put the commands and their outputs in formatted text and/or blockquotes to increase readability.

Fell awkwardly from the elliptic???

@Firelord well Im hoping to retrieve my files. At this point my phone appears to be wiped but Im thinking maybe my files can be found in the Google android backups, basically I dont really have my answer yet... still working on this...

It is possible that your don't have a broken screen but simply a loose connector inside the phone.
You can try to repair it yourself by opening the phone as described in this video:
https://www.youtube.com/watch?v=4pks4idq4YI
Probably you don't need a replacement part. Just disconnect and reconnect the connectors of the flat cable. It worked for me.

When unlocking bootloader device gets reset. All the data is lost. So it was a bad idea from start. You could have moved files using adb if possible.

This is not helpful. OP did not know at first hand what unlocking bootloader would do, but I'm surprised that the bootloader did not issue a warning on the console during unlock.

It is just a warning. He has posted this as a Q&A.

@AshishKafle unfortunately usb debugging was off on the phone so I could not connect via adb. I had to unlock the bootloader to be able to flash the twrp recover to be able to adb in. So I think it was impossible to recuperate the files, Im now hoping to somehow retrieve them from the android backups on Google.


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How do you see Memory usage in Android O?
Prior to Android Oreo I could see Memory usage by going to Settings > Memory but this does not exist any more since upgrading to Android O. Is there any way to see this now or has it been removed completely?

Enable Developer Mode (see here), and go to System > Developer options > Memory

Since accepted answer is not applicable in my situation (there is no "Memory" menu item) (Android 8.0.0, Samsung S8), I want to share another way of getting memory usage info. This shows RAM status and RAM usage by applications.
Settings > Developer Options > Running Services

This answer will only apply when you are a developer, and you have your development PC near.
First make sure that you have USB debugging enabled.
Then on your PC open a shell that can run adb (of you don't know what this is, then this answer is not for you)
Then in that shell run adb shell
This will open a shell to your Android device, within this shell you are running command line applications on your android device.
Now in this adb shell run top -s rss | head -n 20. This will print out a list of about 20 apps sorted by RAM usage(-ish, its not precise).
If you are able to enable ADB Root in developer options (Again, if you don't know that this is, then it is not for you), then you can see more details:
In the adb shell run su. This will elevate your access to the kernel.
Then run procrank.
This will show a lot more info about ram and swap usage.

To show memory usage in android Oreo, first of all make sure enable developer mode in android Oreo
Enable developer mode android Oreo:
Settings > System > About phone > Tap build number 7 times
Now enabled developer options in android 8.0 Oreo.
Go to settings > System > Developer options > Memory > Memory used by apps

Doesn't add anything new compared to @bmdixon 's answer.


text:
When will my device get the Android 8.0 update (Oreo)?
Android Oreo was officially released on August 21, 2017.  It adds features such as picture-in-picture and AutoFill.
You can review the high-level changes at the Android developer website.
Of course, not all devices will get this update right away, even at release; others won't get it at all. Manufacturers and carriers often choose to add their own custom modifications, which tend to delay the official release.
When will each device get Oreo, either officially or unofficially, if ever?
See also:

When will my device get the Android 6.0 update (Marshmallow)?
When will my device get the Android 7.0 update (Nougat)?
How do I update Android on my device? (with links to all other versions)

This community wiki will list all of the known and rumored dates for devices.
If you have an update please edit this wiki here, but make sure to follow the format that's been established, and the following guidelines:

Keep devices in alphabetical order listing the manufacturer and model
Specify if the date is confirmed or rumored and link to the source
If there is an unofficial release, link to the site where it can be downloaded

Phones
Asus

ZenPhone 3: TBD confirmed
ZenPhone AR: TBD rumor

Blackberry

KEYone: TBD confirmed

Google

Pixel: 2017-08-21 confirmed
Pixel XL: 2017-08-21 confirmed

HTC

U Play: TBD rumor
U Ultra: TBD rumor
U11: TBD confirmed

Huawei

Honor 9: 2017-10-30 confirmed
Nexus 6P: 2017-08-21 confirmed

LG

G6: TBD rumor
Nexus 5X: 2017-08-21 confirmed
Q6: TBD rumor

Motorola

Moto G5: TBD confirmed
Moto G5 Plus: TBD confirmed
Moto G5S: TBD confirmed
Moto G5S Plus: TBD confirmed
Moto Z: TBD confirmed
Moto Z Droid: TBD confirmed
Moto Z Force Droid: TBD confirmed
Moto Z2 Force: TBD confirmed
Moto Z Play: TBD confirmed
Moto Z2 Play: TBD confirmed

Nokia

Nokia 3: TBD confirmed
Nokia 5: TBD confirmed
Nokia 6: TBD confirmed
Nokia 8: TBD confirmed pushed

OnePlus

OnePlus 3: confirmed pushed
OnePlus 3T: confirmed pushed
OnePlus 5: confirmed, unofficial on XDA

Samsung

Galaxy A3 (2016): never rumor
Galaxy A3 (2017): TBD rumor
Galaxy A5 (2016): never rumor
Galaxy A5 (2017): TBD rumor
Galaxy A7 (2016): never rumor
Galaxy A7 (2017): TBD rumor
Galaxy C7 Pro: TBD rumor
Galaxy C9 Pro: TBD rumor
Galaxy J1 variants: never rumor
Galaxy J2 (2016): never rumor
Galaxy J3 (2016): never rumor
Galaxy J5 (2017): TBD rumor
Galaxy J7 (2017): TBD rumor
Galaxy J7 Prime (OnNxt): TBD rumor
Galaxy Note 5: never rumor
Galaxy Note 8: TBD rumor
Galaxy Note FE: TBD rumor
Galaxy S6 series: never rumor
Galaxy S7: TBD rumor
Galaxy S7 Active: TBD rumor
Galaxy S7 edge: TBD rumor
Galaxy S8: TBD rumor
Galaxy S8+: TBD rumor
Galaxy Tab S3: TBD rumor

Sony

Sony Xperia XZ Premium (G 8141, G 8142): TBD rumor
Sony Xperia XZS (G 8231, G 8232): TBD rumor
Sony Xperia XA 1 (G 3121, G 3123, G 3125, G 3116, G 3123): TBD rumor
Sony Xperia L1 (G3311, G3312, G3313): TBD rumor
Sony Xperia X Compact: TBD rumor
Sony Xperia XZ (F 8331, F 8332): TBD rumor
Sony Xperia X Performance: TBD rumor
Sony Xperia X (F 5121, F 5122): TBD rumor
Sony Xperia XA 1 Ultra (G 3221, G 3212, G 3223, G 3226): TBD rumor

Tablets
Asus
HTC
Samsung
Other

Nexus Player: 2017-08-21 confirmed
Pixel C:  2017-08-21 confirmed
Smartron SRT Phone: 2017-07-10 confirmed

How bout Lenovo phones?


text:
How to disable the guest feature WITHOUT having to be the only user
How can I disable the guest acount feature on my samsung galaxy s6 WITHOUT having to delete all users (other than me, the owner) or disabling the multiuser feature completely. I want to have users other than me, but I don't want the guest account. My device is rooted.
I found this other question. This question is not a dupe because the answers to the other question do not say how to do it without requiring myself to be the only user.
(My android version is 5.0.2, and my goal is to prevent anyone with physical access from being able to log in using this guest feature, and I don't want to encrypt my device or install custom recovery)

I didnt ever tried to make a multi-user phone, but did you tried making a new user and then delete the guest (that would not remove the multi-user system)?

@TheAnonDevil there is no option presented in the settings to do that.

This one works for me on Android 5.0.1 and 5.1.1
Open a terminal, grant it root access then run
settings put global guest_user_enabled 0

You don't need to add fw.max_users=1 to your build.prop. It prevents more accounts from being created besides disabling guest feature. The above method only shuts off guest while leaving the "more users" option available.

Alternatively, if you don't need dynamically creating & deleting extra users, you can create a few before proceeding.
Add this line to your build.prop.
fw.max_users=2

The multi-user settings will stil be available from your Settings app, but a guest (or any extra account) is kept from being created.

I had to run :
adb shell settings put secure guest_user_enabled 0
adb shell settings put global guest_user_enabled 0
adb shell settings put system guest_user_enabled 0

I did not have to root my device, just use ADB platform-utility. Installation explanation is here.
I am under Android 9

Executing adb shell settings put global guest_user_enabled 0 was enough on my Android 9 tablet (Alldocube iPlay 10 Pro) to remove Guest account from the list of users.


text:
Galaxy S6 Active stuck at No Command/Downloading
The problem as it stands
My Galaxy S6 Active is stuck in a sort of bootloop, except it never seems to attempt a boot. If it was turning on, without any combination of keys, it would go to the "No Command" screen. From there all I can do is force reset (power + volume down) to get it to restart to the same place or as it displays the Samsung splash screen, press volume up + power + home, it goes to the download screen. From the download screen, I can use my pc to flash a rom (that may not be correct) to the device and according to Odin, that is a success but my device freezes on "erasing".
Imgur album with pictures of the accessible screens
Description of the problem when it was booting
At seemingly random times, the device would freeze and the only way to get it to do anything was to reset it. Sometimes it would enter a bootloop but through key combinations, I would be able to get it out. One time after a bootloop, I had the sense to back up the device's storage, so luckily I have that.
What I've done

I have tried wiping the storage in device recovery -- when it was accessible, I can no longer get to it.
I have tried using Kies/Smart Switch emergency software recovery -- but when provided with the model name and serial number they would both crash.
When the device booted, I tried using the standard recovery feature in Smart Switch. I can't remember the exact message but it was something along the lines of "This device does not support initializing"
I have tried using Odin to flash ROMs (again, I may be using this incorrectly) to the device. I have only tried Samsung release ROMs, meaning ones that have not been modified by a 3rd party. I followed the second and third methods of this guide. Odin never throws an error and it always says it was successful. During the device's initilization with this new ROM, it gets to 32% then goes to "Erasing". A few seconds later the animation freezes. I can leave the device here for hours but nothing happens. So I believe more than the animation is frozen.
I tried using ADB recovery via the device's recovery mode (when it was accessible) but from what I can gather, Samsung uses a proprietary ADB interface that would not work with what I was trying to do (I was following method 3 of the previously mentioned guide (I can't post more than 2 links). I would always get a message saying "ADB server out of date".

I may have done more than that but that's what I can recall.
Any help would be appreciated. Even if you know of a better place to post this, let me know.
Thanks


text:
Note 3 stuck on "Odin Mode"
I wanted to check if I had an unlocked bootloader or not and I pressed "Reboot into bootloader mode" in recovery mode.
It now has a black screen with a green android robot saying "Downloading... Do not turn off target!!"
I'm panicking what do I do how do I get out of this mode??

Instead of adding the answer in question as you do in forums, please self answer using the answer section. After 48 hours, you can accept the solution by ticking the green arrow next to answer. Acceptance indicates that this solution worked and is more likely to help others in similar situation

Oh okay, thanks man I'm new to this stack overflow thing. Thanks!

I fixed it. Power + vol up + home ( pressing all three simultaneously)  should work. Hope this can help someone else who gets stuck!

Actually, an easier way would be to just hold the Power button until the device reboots. You may want to include the above in your answer.

No, I tried that it just came back into Odin mode.

This is odd. What device is it?

Samsung Galaxy Note 3, SM-N900W8


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Forgot pattern for my old tablet; no recovery mode available, ADB key not verified (new computer)
I have a 2013 Nexus 7. This nexus 7 is rooted and has an unlocked bootloader but however has no recovery option. (When the device was rooted for some reason it removed the recovery and now has no recover option. Device simply says no recovery).
Now I had to store it when I moved living locations and forgot about it. When I opened the container after about 2 years and found the tablet I then attempted to open it. However when I stored it I realized I HAD SET A LOCK SCREEN PIN NUMBER ON IT! I have purchased a new computer since then so the computer doesnt have the USB debugging key on it for ADB to work on the tablet and I cant unlock the tablet to accept my new computer because I forgot the lock on it!
I am even willing to do a factory reset but I cant even do that because there is no recovery on this tablet. Is there ANYTHING I can do to get this lock screen off?? Hacking the software, programs, factory resets, hard resets, ANYTHING will work.
Anyone have any ideas?

Since the bootloader is unlocked you have a variety of options to pick from and they don't require ADB.
Flash the recovery image to do factory reset
You can use fastboot to flash a compatible recovery image. You can either pick the stock recovery image from official source or choose a custom recovery like TWRP.
When you're in fastboot mode, issue these commands in your console:
fastboot flash recovery FILE
fastboot reboot

Replace FILE with the location where your downloaded recovery image exists.
Now you can boot into the recovery mode and do the factory reset.
When recovery image still doesn't work
If recovery image still doesn't work for you, issue these commands in fastboot mode to factory reset the device.
fastboot format data
fastboot format cache
fastboot reboot

It is perfectly possible to bypass the lockscreen with any credentials but I lack the time to re-test this.


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How do I assign an action to long pressing the home button?
I want to fix it so the home button long press kills a particular app. I can't see the option for home long press in Tasker or Macrodroid.
Galaxy S5, rooted, CM Marshmallow, Xposed installed.

Xposed Additions allows modifying long-press behaviour, but executing more complicated actions is a bit out of it...

Additions can execute Tasker actions, so this gets me close. However, tasker won't kill the app successfully

Macrodroid doesn't offer an action based on  home key trigger. Macrodroid developer in app forums says

It's impossible to create such a trigger because the home button is a fundamental part of the OS and there is no way to intercept the button press.

I don't know  Tasker, but guess the same limitations would apply, so you would need to find an alternative way. One method below:
Since you are on CM, you can use Gravity Box Xposed module
To kill foreground app
Navigation keys action → Home key → long press action → Kill foreground application
To kill a particular app - combination of Gravity Box and Macrodroid
Navigation keys action → Home key → long press action → Custom actions → toggle applications to reveal shortcuts → Macrodroid Shortcuts → Add new macro
Trigger → Empty Trigger
Action : Kill application → choose application from drop down menu

If your ROM offers you navigation bar, you can add a custom key from navigation bar tweaks and assign similarly


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How to activate vibration on call connection
I bought lyf water f1 phone at that time vibration on call connection was working by default. But now suddenly it is stopped .I don't know why I want to restart it again same feature could anyone help me regarding this . Os is marshmallow

go to Settings->Sound->(enable)Also vibrate for calls(Option)


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zsh scp completion of remote files doesn't work when running SSHHelper
Running SSHelper is a great way to access files on your phone. But completion of remote files (scp and rsync) using zsh doesn't work though. While using sshfs is a workaround but sometimes you just want to pull/push a quick file, it's not really satisfying.
Where lies the culprit, and how can I get file completion working properly via zsh?

The culprit is android's crippled ls command. Zsh's completion run ls -d1FL which /system/bin/ls doesn't understand.
A way to fix this is to edit /data/data/com.arachnoid.sshelper/home/.ssh/environment such that /data/user/0/com.arachnoid.sshelper/bin is the first entry in PATH. (SSHelper ships with a more complete ls)
Note that SSHelper might rewrite this file on updates?

Nice detail, thanks! Speaking of updates: if you use F-Droid, you can find the app in my repo (it uses the devs signature, so you can simply update what you got from there). And besides, as you've identified the culprit as the pre-installed ls command: was that the "stock" one, or would the ls provided by Busybox have the same limitation?

busybox ls is sufficient I think. Ie. busybox ls supports at least some of the flags that the system doesn't.


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How to enable softkeys on a rooted phone with capacitive buttons?
I have a Samsung Galaxy Tab A 10.1 tablet and the capacitive buttons are extremely annoying - I keep pressing them accidentally all the time while holding the tablet in landscape orientation. The tablet is running Android 7.0 and is rooted with TWRP/SuperSU.
It's easy to disable the physical buttons through various apps, but how can I enable the native softkeys? There are various apps that simulate the software buttons in the Play Store, but they're all glitchy.
I've tried adding qemu.hw.mainkeys=0 to the build.prop file, but after doing that the tablet gets stuck at the black screen when rebooting.

The getting stuck problem is probably because the stock kernel has detection for /system modification.

@AndyYan any way to override that?

Custom kernels/ROMs, though that might be far off what you expected to get something this simple. Perhaps I'm wrong and there is a simpler approach - wait for others to put forward alternatives. // As for non-native solution, LMT Launcher had always worked well for me, and doesn't occupy a bar of screen space.


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Change default account in "Add new contact"
I have several accounts on my phone. When I add a new contact, my Google/Gmail account is always preselected, but I always want to add my contacts to another one, and quite often I forget to change the account.
Is it possible to change the default account so I don't need to switch account every time I add a new contact?
Phone: Lenovo Moto G4 Plus with Android 7.0

I'm not very sure but perhaps it would be help be for you go to Settings->Accounts->Google->(turn off) contacts.

It's something different to turn off a contact storage or to change the default, so that's unlikely to be the answer. Apart from which: doesn't this only turn off synchronization?

After that you can turn on contacts storage into another contact.

So with a few more words, what you suggest is: first turn off Google contacts storage, then add a new contact (should ask again for "default storage"), then turn Google contacts back on? Have you tried that? While it sounds reasonable, the place you describe IMHO just toggles sync.


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Anyway to split apps sharing an UID?
For a while, I had an exclamation mark instead of a signal status in the top bar, and some apps didn't realize they were connected to Internet when other worked perfectly.
Thanks to AFWall+ logs, I found the issue.
I need to allow access to an app called com.android.engineeringmode.
But this app is tied (in OnePlus 3) with some others, as you can see in this screenshot :

I'm OK to allow access to EngineerMode, but certainly not to all this bunch of apps (especially camera or fingerprints services).
After searching the web, I found that all theses apps are linked in /data/system/packages.xml using the sharedUid 1000. But it is said to never change the UID of an app when it's shared (I didn't really get why).
I'm using the stock ROM (OxygenOS 3.2.8) from OP3, but rooted (got Xposed an Xprivacy too), so it's Android 6.0.1.
Is there any chance I can allow Network access to EngineerMode only ?

Even if you change the sharedUID in that XML file, the modification gets lost after a reboot. Back to square one.

While iBug's comment seems a better answer to the question, my real need was to have a correct Internet access detection over the system.
In order to fix my issue I had to open an adb shell, type in
settings put global captive_portal_detection_enabled 0

Then reboot. The exclamation mark went away and problematic apps behave better now.
For the record, this prevent a check on Google's servers. This check was impossible with my firewall's rules.
Thanks to Dan Hulme and iBug for their help.

In case it's not obvious to other visitors, note that this disables the detection completely, so you won't get the "Sign in to Wi-Fi network" notification when you connect to a captive portal.

I don't think it's possible to change this without recompiling the ROM. You can't change the UID of apps after they're installed because they won't be able to access their files any more, and because it will confuse the app permissions system.
Maybe there's some other way around the problem with Xposed, but I don't know about that. It might be possible for an Xposed module to detect the exact call the package is making (to distinguish it from the calls made by other packages in the same process), and mark it for AFWall to allow it. That way you wouldn't need to split up the apps at all.
An alternative might be to find where it's trying to send traffic to, and whitelist that address for that process. Again, this would solve the specific symptom without splitting the apps. If it's the captive portal detection, it's probably http://client.android.com/generate_204.

Thank you for this answer, I've been thinking of using a custom script which is something quite easy to do with AFWall+, but I couldn't think of a way to mark properly the request. I'm going to test if I can whitelist the captive portal detection and see if it solves my issue.

Using adb shell I just removed the check with the command "settings put global captive_portal_detection_enabled 0", then reboot. It appears that fixed my issue, thanks for pointing out the captive portal detection thing.

And by the way, thank you too for the brief explanation regarding why I shouldn't try to slip the package sharing one UID

Sorry but this answer seems confusing and... wrong.

@iBug Reading it back, I realise it sounds like recompiling the ROM without any source changes will fix it, which is obviously untrue. Is that what you're  referring to? If not, please be more specific.

@Stopi I'm glad it set you on the right track. It would be great if you write up the steps you took, post it as an answer, and then accept your answer in place of mine.

Well, thinking of recompiling everything obviously involve to make some changes in the code, there's no need to say it. This is my first post on this site, I'm going to do what I've been told.

...I can't accept my own answer before 2 days.

The solution that Dan Hulme has provided is right and I'd like to make it clearer: You have to re-compile the ROM but wait! Open the source for EngineerMode and look for something in AndroidManifest.xml like sharedUserId="android.uid.system" and change it to something else.
That's the fundament of a shared user ID. You must modify the app so that it doesn't require a shared UID anymore.

You may be right, I didn't really think of this because I didn't want to bother recompiling everything (and re-install all my apps...). The chosen solution really fixed my issue in a best way. Maybe the problem here is I've asked for the wrong thing, trying to go one step forward and wanting to split apps tied when what I really wanted was to have Internet access detection behave correctly (I hope my poor English can be understood). Anyway, thanks for your interesting answer.


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LineageOS stuck on boot in Moto G1 due to WiFi error
I installed LineageOS on my Moto G1 (falcon) and after using it for a couple of weeks my phone restarted and got stuck on boot. I cleaned the cache in recovery mode but it didn't help. Afterwards, I reinstalled LineageOS and the problem went away but it happened again after a couple of weeks. Using logcat during the boot process gives me the output below. It seems to be stuck in WiFi initialization due to an error. The WiFi initialization error keeps repeating every couple of minutes. Has anyone seem something similar or has any possible workaround? I don't want to reinstall the OS every now and then.
Regards.
- waiting for device -
--------- beginning of main
02-15 09:13:01.048   178   178 W auditd  : type=2000 audit(0.0:1): initialized
02-15 09:13:02.560   178   178 I auditd  : type=1403 audit(0.0:2): policy loaded auid=4294967295 ses=4294967295
02-15 09:13:02.560   178   178 W auditd  : type=1404 audit(0.0:3): enforcing=1 old_enforcing=0 auid=4294967295 ses=4294967295
02-15 09:13:06.111   189   189 I         : debuggerd: starting
--------- beginning of system
02-15 09:13:06.194   190   190 I vold    : Vold 3.0 (the awakening) firing up
02-15 09:13:06.195   190   190 V vold    : Detected support for: exfat ext4 f2fs ntfs vfat
02-15 09:13:06.223   190   195 D vold    : e4crypt_init_user0
02-15 09:13:06.223   190   195 D vold    : e4crypt_prepare_user_storage for volume null, user 0, serial 0, flags 1
02-15 09:13:06.223   190   195 D vold    : Preparing: /data/system/users/0
02-15 09:13:06.230   190   195 D vold    : Preparing: /data/misc/profiles/cur/0
02-15 09:13:06.231   190   195 D vold    : Preparing: /data/misc/profiles/cur/0/foreign-dex
02-15 09:13:06.232   190   195 D vold    : Preparing: /data/system_de/0
02-15 09:13:06.233   190   195 D vold    : Preparing: /data/misc_de/0
02-15 09:13:06.235   190   195 D vold    : Preparing: /data/user_de/0
02-15 09:13:06.236   190   195 D vold    : e4crypt_unlock_user_key 0 serial=0 token_present=0
02-15 09:13:06.240     1     1 I vdc     : 200 192 Command succeeded
02-15 09:13:06.277   196   196 I /system/bin/tzdatacheck: tzdata file /data/misc/zoneinfo/current/tzdata does not exist. No action required.
02-15 09:13:06.346   197   197 W batt_health: type=1400 audit(0.0:4): avc: denied { read } for uid=0 name="power_supply" dev="sysfs" ino=5990 scontext=u:r:batt_health:s0 tcontext=u:object_r:sysfs:s0 tclass=dir permissive=0
02-15 09:13:06.353   197   197 E BHD     : Could not open /sys/class/power_supply
02-15 09:13:06.353   197   197 E BHD     : acPath not found using default
02-15 09:13:06.353   197   197 E BHD     : usbPath not found using default
02-15 09:13:06.353   197   197 E BHD     : batteryPath not found using default
02-15 09:13:06.353   197   197 E BHD     : Battery not valid
02-15 09:13:06.353   197   197 E BHD     : Failed to validate battery after 1 attempts
02-15 09:13:06.354   197   197 E BHD     : NVM Read - Can not open /pds/batt_health/batt-0123456789abcdef_0, errno = 2 (No such file or directory)
02-15 09:13:06.354   197   197 E BHD     : NVM Read - Can not open /pds/batt_health/batt-0123456789abcdef_1, errno = 2 (No such file or directory)
02-15 09:13:06.354   197   197 E BHD     : No valid NVM files found
02-15 09:13:06.389   199   199 I sysinit : Running /system/etc/init.d/0000liveboot
08-18 20:22:15.277   682   961 I WifiHAL : Initializing wifi
08-18 20:22:15.281   682   961 E WifiHAL : virtual int WifihalGeneric::handleResponse(WifiEvent &): QCA_WLAN_VENDOR_ATTR_FEATURE_SET not found
08-18 20:22:15.281   682   961 E WifiHAL : nl80211: requestResponse->nl_recvmsgs failed: -5
08-18 20:22:15.281   682   961 E WifiHAL : get_firmware_bus_max_size_supported: requestResponse Error:-95
08-18 20:22:15.282   682   961 E WifiHAL : Failed to get supported bus size, error : -95
08-18 20:22:15.460   682   995 I WifiHAL : event received NL80211_CMD_VENDOR, vendor_id = 0x1374, subcmd = 0xa
08-18 20:22:26.892  1400  1577 I WifiHAL : Initializing wifi
08-18 20:22:26.895  1400  1577 E WifiHAL : virtual int WifihalGeneric::handleResponse(WifiEvent &): QCA_WLAN_VENDOR_ATTR_FEATURE_SET not found
08-18 20:22:26.895  1400  1577 E WifiHAL : nl80211: requestResponse->nl_recvmsgs failed: -5
08-18 20:22:26.896  1400  1577 E WifiHAL : get_firmware_bus_max_size_supported: requestResponse Error:-95
08-18 20:22:26.896  1400  1577 E WifiHAL : Failed to get supported bus size, error : -95


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Clearing user data for Google Play Services
I am using Samsung Galaxy On7, Android 6.0.1.
My phone internal memory is quite small, 8GB. Moreover, apps like MS Word and Excel, which can be moved to sd card, come inbuilt, as a result of which I cannot move them to sd card. So, I clear user data for apps as much as possible, so that space can be freed up.
Now, I see that Google Play Services is using up 68MB of data. I want to clear this data, but as this is one of the basic apps on which the phone runs, I want to know what might be the ill consequences of clearing this data. Will apps no longer run or I'll face grave troubles if I clear this user data?

That's sad. I would have really liked to force move apps to sd, but I don't want to root my phone. Anyways,  thanks for the input.

OK. I'll keep that in mind.

Yes, experience comes handy in these cases like mine. :-)

@Firelord: Didn't think to check before answering :( - upvoted your linked answer

@beeshyams no worries. :)

From experience ;
You won't face any grave troubles or troubles for that matter -worst case being you may be required to log in again into Google accounts. But this isn't going to fix your storage problem as it gets recreated
But don't delete Google Services Framework data. Your Google based apps will stop working and you may need to install apps all over again or do a factory reset / flash  ROM again ( this was the option I chose when things turned troublesome )
Thanks to Izzy for additional inputs on Google Services Framework

Google engineer explains why you shouldn’t clear Google Services Framework data | TalkAndroid.com. That would essentially reset the ANDROID_ID assigned to the device, so a lot of apps will feel like "factory reset". Especially those using GCM might behave strangely then (need to re-register with the corresponding servers as the ID changed)
ANDROID_ID is set on first start and usually lives until you do a factory-reset; details can be found in my (Izzy's) article Android Identifiers: How Android devices and their users are identified.

68 MB isn't much for Google Play Services.  You would need to look at other apps that you can get rid of to create storage - social media apps come to mind

Oh: And next to "social media apps", Maps tend to keep large hunks of data (mostly map tiles for offline use). For cleanup organization, our isufficient-memory tag-wiki is a good starting point.

@beeshyams all my social media apps are disabled,  and take no more than 15kb of data. For your information, I'm not on social media except whatsapp and SE, though I don't consider the latter a social media.

@lzzy my GMaps data always remains close to 0 :-)

In which case, it may help to look at the pointers provided by Izzy including the tag of insufficient memory


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Space used in internal memory but nowhere to be found
I own a Samsung Galaxy S5. I noticed that there is not much internal memory left (ES File Explorer reports 8.54 GB used out of 11.56 GB so about 3 GB left). Also, connecting my phone to my Windows 10 PC reports a consistent amount of free space.

3 GB Left according to ES File Explorer and Windows File Explorer
The strange thing is this: I can't seem to find where those 8 GB of files are! If I drill down by double clicking on my internal memory and select all the files and folders in it, the number of used bytes is completely different! Only 556 MB!

I have gone and make sure that my View Settings on Windows does not prevent me from seeing hidden and system files... so, where are the files that are taking all the space in the internal memory?
Anybody with any ideas willing to help would be appreciated!

Related, and useful to dig into your case: Android “Internal Storage” used but not reported (a bit old, but the hints are still true). Also helpful, hopefully: my list of apps for Storage Analysis.

Android (MTP, I should say) ignores Windows' setting of showing system files. What the computer sees is merely the content of the internal storage accessible to a non-root user. What is killng your space are all the files under /data, which encompass info used by the system to list your apps, your apps themselves and their data.

Most of that space is used by apps (not visible on n windows, but visible on phone with root) and app's data, sometimes can be accessed if it's stored outside of /data partition.

I decided to keep looking for places that did not go reported by Windows (those reported by ES File explorer as "Other") and stumble upon a good candidate. In my case it was Google Maps.
Turns out I had a few "offline areas" downloaded on my phone from a recent trip and that was eating a full GB of internal space.
Deleting those maps fixed my problem.
I guess what I learn from this exercise is to always open "Setting" --> "Internal Storage" --> "Used Space" --> "Apps" to get to a screen called "Storage Used by Apps" that list the full set of applications on my phone and the amount of memory being used (from high to low). That should help me get started in pinpointing good app-candidates for "cleaning".

authors: Једноруки Крстивоје


text:
What makes flashing ROMs risky?
I would like to play with developing Android ROMs for learning purposes and for maybe I can fork my current ROM and change interesting stuff in it.
I would rather be not happy at all with a bricked device, but how likely is that to happen?
As far as I know,  if the bootloader is untouched, flashing even garbage should leave the device repairable since one can still go in flash mode and flash a new rom because the bootloader is fine. Right?
Also I presume hardware can't really be damaged by bad software, can it? (I need a compelling reason if you say yes)
So theoretically, my device can't really break by flashing and trying a custom ROM even if its faulty or even there happens an error during flash, no? (given I don't touch the bootloader)

Usually, ROM devs add certain checks called asserts in the zip's updater-script, which abort the installation if your device is not confirmed as compatible. Obviously, that's not a luxury you do have if you create a ROM yourself (if you don't add the checks manually, that is). To summarize, if you build your own ROM with your own zip, you must take care not to overwrite the bootloader, overwrite only the /system partition, (optionally) overwrite /dev/block/platform/msm_sdcc.1/by-name/boot to install a custom kernel and pay great care not to flush your partition table by mistake.

@DeathMaskSalesman ..and does the device really brick if its installed even if its incompatible? Also hmm flushing partition table..

Flushing partition table, yes. Try something like dd if=/dev/null of=/dev/mmcblk0 only if you wish doom upon your handset. Moreover, your device should merely soft-brick if you flash incompatible firmwares, provided that nothing but /system, /boot and optionally /data gets overwritten. To put it in another way, until your bootloader and/or partition table are busted, there's nothing you can't recover from.

As Death Mask Salesman pointed out, you need to be sure that the flashing process itself doesn't overwrite the partition table or the bootloader. But even if the flashing itself doesn't cause an unrecoverable problem, it's still possible for a broken ROM to break the hardware of the phone.
Here's a real-life example from when I worked on ROM integration. One of my colleagues bricked the development hardware we were working on by flashing a ROM where the kernel had had the CPU throttling and thermal cut-out disabled. The development board ran with the CPU at max speed for a couple of minutes and then melted the SoC.
Hardware can very much be damaged by drivers that have been edited or compiled with the wrong options. Overclocking the CPU or GPU (a popular feature in custom ROMs) carries its own risk of overheating - especially if your phone is slightly off-spec. Some kinds of screen backlight can be damaged by running them too hard, which the driver prevents in normal use. Also, some components such as NFC chips and secure elements have anti-tampering "fuses" - if you blow one of those by accident (by writing to the wrong hardware register), it might be irreversible.
This is why rooting or flashing a custom ROM voids the warranty.


text:
Question regarding Google Play app compatibility check, x86 vs. ARM architectures, etc
This is more of a hardware question than anything, but it has to do with Android.
I saw on this question, somebody saying that Android apps were architecture independent, and should run on ARM/ARM64/x86 platforms.  Another reply was saying that the APK files can have architecture-dependent libraries, but not code themselves.
Now, here's where my question comes in.
I was looking inside the contents of an APK file, and I noticed that the only "lib" folder was for armeabi (32-bit ARM).  But, my phone has a 64-bit ARM processor (aarch64, with the arm64-v8a instruction set), and the app runs fine.  Hmm... how does that work?
So I thought I would try a few other things.
I installed Android-x86 in a virtual machine, logged into a Google account, and downloaded a few games.  The one in question, which only has the "armeabi" folder, showed up as being compatible (as in, the install button was there) - but it immediately crashed after opening.  I know there are some games that fake-crash on rooted devices (and Android-x86 comes pre-rooted), but the one in question is not one of them.  I've used it on CyanogenMod on a real phone and it doesn't care.
But something else I noticed: at least one other game I was looking for did not show up - the game Super Mario Run from Nintendo.  See my screenshot here:

Notice under "Library" there's no option to install it, and if you look at apps published by Nintendo, it's just not in that list (which means the Play Store is deciding my hardware is incompatible, and basically hiding it).  But, it DID seem to think my Android-x86 VM was compatible with the OTHER games, which just crash immediately.
So I decided to try something else.  I picked up a cheap Intel Atom-based processor (one of the Insignia brand ones at Best Buy, as it's all you can get these days that's carried in stores).  Run CPU-Z on there, you can confirm it's x86 and not ARM.  Super Mario Run shows up, however, and works fine - so do the other games with only "armeabi" libraries!
What piqued my curiosity is that, according to the specifications of the Intel Atom x3 processors, they actually have "ARM" GPUs.  (Specifically the PowerVR 6500 series)
CPU-Z shows this too, where it says the CPU is x86 but the GPU is ARM.  I found some other press releases from 2015, when they introduced the Atom x3 line, about the two being combined.
So in this case, is the tablet only able to run these games because its GPU is ARM? If so, what's the actual significance of the CPU portion being x86? I'm completely confused at that.
I was considering tracking down a used older tablet with an Intel Atom, that still used the "Intel HD Graphics", and was not a hybrid ARM chipset.  Something like a Toshiba Excite Go.  But this is really just to find out if it would act the same as Android-x86, or if those apps would work.  I'm curious what the incompatibilities/crashes are - is it just because Android-x86 is a hackjob and not official? Or do the apps with only "armeabi" libraries truly only work on ARM processors and somehow the Insignia can run them because of its hybrid chip?
(As far as my phone having ARM64, it might have some sort of compatibility layer much like x86-64 for running 64-bit PCs? I don't know much about ARM but I know in the case of AMD64, it's an extension on top of the traditional x86 architecture so you can natively run both x86 and x64 programs - also why they won over Itanium, which was not like this.)
Lastly, as far as the Play store recognizing whether an app is compatible or not - I would assume the developer doesn't have an actual whitelist of all devices the app can run on, that would be incredibly stupid and any time a new Android device came out, it would cause issues.  So how exactly does that work? Do they provide minimum required RAM/CPU/resolution, things like that? Based on architecture as well?  I know I've seen some apps that show as being incompatible with a larger-resolution tablet (like the Samsung View) that do work on phones, and always thought that was strange.
Edit: One of the suggested threads from this one was actually about how the Play Store knows an app is incompatible, based on the app's manifest.  And as much as it might make sense that it would be incompatible if it requires GPS and your device doesn't have GPS, or Bluetooth, etc., that doesn't really explain why an app would install fine on a 7" tablet but not a Samsung View.  That isn't the fastest processor in the world, but it's better than some of the older 7 or 10" ones...

Regarding Nintendo games on Android, it does seem that N likes to restrict its software, allowing it to run on SafetyNet-compliant devices only.

Possible - as I know Pokémon Go uses SafetyNet (though that isn't Nintendo themselves), but Pokémon Go is installable from Google Play on Android-x86 - you just obviously won't be able to use it.  Miitomo is the same way as Mario Run, it will just crash right away on a rooted device - but Miitomo does show as installable on Android-x86 while Mario Run does not.  That's why I'm curious.

Maybe Mario Run does enforce mandatory use of the touchscreen? No clue, otherwise.

Ah, good point.  I mean, you do need the touchscreen for the game to work since it's controlled by tapping ... but with Android-x86 emulating a tablet, your mouse and keyboard work anyway, and left-clicking the mouse is (I thought) equivalent to tapping.

If my guess holds, I would say that the Play Store can discern between a real touchscreen and an emulated one. It may be that the game specifies a certain property inside its AndroidManifest.xml (a XML file describing an app, found in any APK), and that the Play Store doesn't allow the installation because of this (again, it could be, but mine is speculation).

Right, right, I totally get you.  What's strange is, I was trying some of those "hardware info" apps, and one of them shows my Android-x86 VM as having both x86 and armeabi v7 instruction sets ... um, what? How?! Perhaps that's why it let me install some of the other Nintendo games that just immediately crashed, as the one I was experimenting with, inside the APK, only has armeabi libs.

I'm afraid I don't have a decent answer to your question. Still, I'll upvote it, as the topic you brought up is quite charming.


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How to run app on one device from another device?
Is there a way to run an app (for example Gmail app) on a different device in the same wifi network? Conditions:

Two Android smartphones are in the same with network.
The devices are controlled by the same person.
The user runs the script/app on one device that starts Gmail app on the other device.
There is no Internet connection in the network. Just the connection between the devices via WiFi.
No root access to both devices.

Use remote ADB.
First connect both devices with an OTG cable and a regular cable (or a C to C cable if applicable), and start an ADB shell, then type:
setprop service.adb.tcp.port 555
stop adbd
start adbd

You may want to run ifconfig to get the IP address.
Then you can disconnect the phone from cables and use wireless ADB. On your controller phone, run
adb connect xxx.xxx.xxx.xxx:5555
(tap [Authenticate] on the first phone)
adb shell monkey -p <package> -c android.intent.category.LAUNCHER 1

There is no way to use root access on the second device. I've edited the question.

Root is not required actually.

Ok, I will try it. Will this work with multiple devices controlled by one?

Repeat the adb connect line multiple times with different IPs.


text:
Get SIM card connection info
If I want to know if I am connected 2G, 3G or 4G, how do I check that on Android?
I don't seem to have any default SIM-related app on my phone, nor does the SIM setting screen give much information other than APN details (APN type says "default").
I'm using FlymeOS 6.1 (Chinese ROM based on 5.1 Lollipop).

There is information under About phone->Status->SIM Status.
The relevant field is Cellular network type.
3g if:

UMTS
HSPA
W-CDMA

2g if:

EDGE
GPRS
GSM