Yes, Berks 3 has MFi controller support!
Berks 3 on iOS does support controllers and is compatible with the MFI standard.
Once these have been collected, you gain access to the Inner Sanctum.
Once inside, 10 more keys must be collected before you gain entry into the Berks' Sacred Treasure Chamber.
Extra Information: Play left or right handed, your first touch becomes your direction control and your second touch activates your blaster.
You terror tank remains stationary whilst firing and you can direct your blaster with the first touch.
Berks 3 supports MFi controllers.