This is the app called Franco Kernel Manager, one of the best kernel managers that are out there… Even when it was outdated (which I think that’s the cause it got booted from the PlayStore?).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!
The app is adfree and not spammy. Can’t talk about the Website though, I haven’t browsed the internet without good content blockers for the last decade