app installed to /system/priv-app won't run

Prerequisites:

• a rooted Rockchip-based China tablet device running Android 6, patched to disable SystemUI




• own-developed app which declares LAUNCHER category and is intended to take full conrol of the device

What am I trying to achieve:

install the app as a system app to avoid handling SDK 23+ permissions

What have I done so far:

• installed the app regularly via Android Studio


• moved the app to /system/priv-app:

(root)

ls /data/app/my.package.name-1

 base.apk

 lib

 oat

mount -o rw,remount /system

mv /data/app/my.package.name-1 /system/priv-app/AppName

ls -la /system/priv-app/AppName

 -rw-r--r-- system
system
 2464934 2017-12-08 11:32 base.apk

 drwxr-xr-x system
system

2017-12-08 11:32 lib

 drwxrwx--x system
install

  2017-12-08 11:32 oat

reboot

What is the problem?

It seems the system is not aware the app exists: it does not run on boot (which it perfectly does when installed as a regular app) and I am unable to launch it manually:

root@rk312x:/ # am start -n my.package.name/.ui.MainActivity

Starting: Intent {
 cmp=my.package.name/.ui.MainActivity 
}


Error type 3

Error: Activity class {
my.package.name/my.package.name.ui.MainActivity
}
 does not exist.

What am I missing?