问题
One of the biggest school has its own Android tablets which distributed among several branches and it's already with the students a long time ago.
We need to develop an app and put it in the play store normally and all the students have to download the app but this time we need the app to run as a system app and take the full control of the devices ( without rooting the device ) we need to prevent some malware apps from installing, access the wifi, mic, and camera, etc so we make sure the students use the tablets in studying and exams only.
We search a lot and found that most of the answers are for android 5 and earlier. but there are many apps in the play store doing so.
So how to develop the app to run as a system app without rooting the device and without installing a custom ROM?
回答1:
You cannot install an app to any mobile as System app because system app should be signed with the same key as of the firmware apps. If not then it will be treated as non system app and it should maintain the permission restrictions. You can see some basic difference between System App and User App at link.
Regarding Citrix, as per my knowledge this is not a fully native app rather it manages a secure virtual container as app's own environment where it performs all the resource related activities. It does not do anything locally in the physical location such as mobile device. You can get a basic idea about Citrix at link.
As a conclusion, it is not feasible to make your app as System app. But it is possible if you can have legal agreement with the mobile vendor(s) so that the app can be signed with their firmware apps signature.
来源：https://stackoverflow.com/questions/56039718/how-to-convert-an-app-to-be-a-system-app-in-android-5-0-without-rooting-the-dev