I have rooted K3 note and I updated all my google apps. Then try to switch the app as system app. While most of them are working properly, some apps like chrome, maps, hangouts don't start. When u booted the system a black screen with error message poped and said: app not installed properly, please reinstall the app form google play. And whenever I tap on them it showed the same message again. However as user apps they work properly.