GSam Battery - Root Companion is an app by GSam Labs in the Tools category, listed since at least July 2015. It has no native code, so it runs on any Android processor.
It asks for 3 permissions, none of them sensitive.
What's new in v1.5
1.2
• Added a backup/restore script for Cyanogenmod (and derivative) users. This gets installed during the app install and will should restore the app after a ROM update.
• Added the ability to read some system files for additional statistics.
Description
From the listing uploaded by “piratasalfaro”.
Enables full Battery statistics on KitKat based Android devices for GSam Battery Monitor.
Unfortunately, Google has removed the ability in KitKat (4.4) for non-system applications to access battery statistics. This companion app restores this function by running as a privileged system application. Root access to your device is required. GSam Battery Monitor works fine without the root companion, however this app adds additional statistics.
Why Install?
• If you are using GSam Battery Monitor on KitKat (4.4) or later, and the app informs you that it is unable to retrieve battery statistics, you should install this app.
What does this do?
• This runs as a system privileged app and provides the caller access to the Battery Statistics that - prior to Android 4.4 - used to be accessible to any normal application.
• This also provides the ability to read the content of small files to which the regular battery monitor has no access - wakelock files for example.
Is Root really required in KitKat?
• Unfortunately, root is required to copy this app into /system/priv-app, which allows this app to run as a privileged system application. There are other alternatives, but all of them require root.
Is this safe?
• Yes - the code is open source, and very simple. GSam Labs believes that any app that you install as root must be fully open source to allow you to inspect the application and ensure it doesn't do anything malicious. With that principle in mind, you can find the source here: https://github.com/GSamLabs/GSamBatteryMonitor-RootCompanion
* NOTE: If you are unfamiliar with what 'root' means, this app is not for you.
How do I install it?
• Install this just like any other application from the store. Once installed, there will be a button that will copy the app to /system/priv-app, and prompt you to restart your device.
• Flashable Zip: You can find a flashable zip in the github repository under the RecoveryInstallImages directory (http://goo.gl/0zcqbL). Flash this in the recovery of your choice. This should work for most phones, but since the google update binary differs between devices, there is no guarantee.
• NOTE: This only works if you have root access to your device!
How do I uninstall it?
• Once a system app is installed, the normal uninstall procedures don't work. To uninstall this app once it is a system app, simply launch the app and click on the Uninstall button.
Can I remove the icon from the launcher?
• Yes - you can! Once you have the app properly installed, open the app and select the 'Remove from launcher' checkbox. If you need to open the app in the future, simply go to GSam Battery Monitor, and select the 'Launch Root Companion' menu option, or go to the Google Play Store, look up the root companion, and hit the Open button.
Will I need to re-install after an Android update?
• Yes - android updates will typically remove any non-stock apps from the system app-priv directory, so you will need to re-install this app after an update to Android.
Will this work with other battery monitors?
• Not by default - it is up to the author of the battery monitor whether they would like to leverage this tool or not. GSam Battery Monitor of course is fully supported.
Help! Things don't work after installing this!
• Like all root applications, some care must be taken by the device owner when installing this app. This application is free and open source. GSam Labs is not responsible for any problems, though we will try and help - simply contact us via the Support link.
Credits
• Thanks to stericson for providing such a great RootTools library (http://code.google.com/p/roottools/)
Security & authenticity
Security rating: Trusted
Signing certificate
Certificate issued to “GSam Labs”The developer's name — though anyone can put any name in a certificate.
Uploaded by “piratasalfaro”Bronze tier · 866 followers · uploading since 2014
Scans and ratings come from the source store; the certificate comparisons are AAPKs's own, made from the files' published signatures. AAPKs doesn't scan files itself — compare the MD5 and signer after downloading.
Permissions (3)
GSam Battery - Root Companion requests 3 permissions, none of them sensitive.
GSam Battery - Root Companion APK: questions and answers
Can I install this APK over the version I already have?
Only if it is signed with the same certificate as the copy on your phone and isn't an older version. If Android says “App not installed”, the certificates differ; uninstalling your copy first works but deletes its data unless it is backed up.
Is the GSam Battery - Root Companion APK safe?
No one can promise that a file is safe, but some things can be checked. The source store rates this file Trusted. After downloading, check that the file's MD5 is 08e2f435fd7b1c96338c06ac2cfa4a1e.