Requirements
*.Your Android device must be rooted.
.*.A root access file manager of your choice.
We will be using ES File Explorer for the purpose
*.The APK file for the app you want to install as system app.
Important: Make sure to allow any SuperUser permission requests that you may get during these steps..
Procedure1.Configuring ES File Explorer for root read/write access (required only once):
1.Launch ES File Explorer, press Menu and tap ‘Settings’.
2.In the settings, enable the ‘Up to root’ check box.
3.Further down in the settings, enable ‘Root Explorer’ check box.
You will get a warning that you should confirm.
4.You will then get the Superuser permissions request that you must allow.
5.Finally, enable the ‘Mount File System’ check box, and press the back key to get back to the explorer interface.
ES File Explorer is now configured to work as a root explorer.
You do not need to do this again on the same device now, unless you uninstall ES File Explorer, perform a factory reset or install another ROM.
2.Finding the APK of an already-installed normal app (skip to step 3 if you already have the APK):
1.First of all, install the app from Play Store, if you haven’t already done that.
2.Launch ES File Explorer and go to /data/app. (You may have to press the back button to get to / first).
3.If you know the icon of the app, you can easily find it here.If you are having trouble finding the app here due to the confusing names or because of having a lot of apps installed, just search for the app in Google Play Store in a web browser and look at its Play Store link for the name.
The file name will basically be the part after? id=in its market link (and before any other question mark that may or may not appear in the link).
For example, the market link for ES File Explorer is
https://play.google.com/store/apps/detai...ndroid.pop
and its APK file in /data/app is com.estrongs.android.pop-1.apk.
3.If you already have the APK of the file that you want to install as a system app, make sure you have transferred it to your device’s SD card if you haven’t done that already.
Also make sure you know the path where you have copied it on the SD card.
4.Once you have located the required APK on the SD card from ES File Explorer, tap-and-hold on its icon till you get a menu, and tap ‘Cut’.
You should see a little blue arrow on the bottom of the screen now.
(You may select ‘Copy’ instead of ‘Cut’ if you are copying a file over from the SD card and want to keep a copy there.
In case of copying an APK from /data/app, always use ‘Cut’.)
5.Now press the back button till you reach / and then browse to /system/app/
6.Tap the little arrow that you see on the bottom of the screen.
It will bring up a pane with the icon of the copied file.
7.Tap on the file’s icon, and it will be transferred to /system/app/.
8.Now find the app’s icon in the list of files there and tap-and-hold on it till you get the menu.
9.Scroll down in the menu till you see ‘Properties’ and tap on it.
You will now see the properties dialog.
10.Tap the ‘Change’ button in front of the Permissions to bring up the permissions dialog.
11.Make sure everything under ‘Read’ is checked, only ‘User’ is checked under ‘Write’ and nothing is checked under ‘Execute’
12.Tap OK on this screen and then on the Properties screen.
Your app’s permissions are now set correctly.
13.Reboot your device.
Your app is now ready to be used as a system app.
