6.0 marshmallow - 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?

Answer

Changing the permissions to -rw-r--r-- and owner as root followed by reboot should fix

But as OP pointed out signature issues need to be sorted out