How to update an app from another app?

Question

Android

You need to programmatically update the application through another application, without user interaction.
Further, the updated application should remain a launcher and have certain rights.
No interaction because it's a kiosk.
The scheme flies in my head:
1) The target application starts when the device boots.
2) Updater.apk is launched from the target application
3) updater.apk checks for updates and, if necessary, reinstalls the application
4) updater.apk programmatically issues the necessary
How to do this?

Answer 1

Installation without user interaction is possible if there is root, or the application has system privileges (signed with the same key with the system and located in the / system / priv-app folder). In all other cases, there will be a standard installation window that requires user activity.
Otherwise, just download the new apk by the application itself and request installation using intents, if you need to do something during installation, there are broadcasts like android.intent.action.PACKAGE_REPLACED.
For autorun to work, the application must be launched at least once manually.