Should systems ui be a apk app or am i hacked

[AC Question]

I know my phone has been messed with by my spouse I'm trying to find out how and where it's located and on yes file manager it said system you are APK are there APK apps already pre-installed or do they need to be installed to have it I think there has been some added on commissions to be able to get into my phone

 

[Golfdriver97]

Welcome to the forums. That app is a preloaded app. Without it, Android would look like the command prompt from the DOS days.