Remember guys, this is why we don't pay for the apps.

This is the app called Franco Kernel Manager, one of the best kernel managers that are out there... Even when it was outdated (which I think that's the cause it got booted from the PlayStore?).

I used it to check the process of my phone and monitor the active and idle drain mostly, I paid for it a long time ago, but now it just fails to check the licence and it doesn't let me use it fully... I think there must be a cracked APK over there...

EDIT:

Fortunately the app is back in the store and hopefully that update version comes soon enough!