Greetings, I recommend using the MAME4iOS project rather than the MAME4apple project. MAME4iOS can
be downloaded from GitHub here: MAME4iOS
MAME4iOS has support for all Apple devices and is constantly being updated. It even supports AppleTV.
It is also based on a more recent version of MAME, V0.139, and has better rendering and audio support
in addition to support for MFi and iCADE controllers.
The project is built from the MAME 0.37B5 core with an all new front end using SpriteKit.
The advantage of using SpriteKit for the front end and OSD is that it can be targeted for any supported Apple device including the AppleTV.
The new project is 64 bit compatible and uses SKMutableTexture as the MAME render surface.
The MAME4apple project is built on the MAME 0.37B5 core as downloaded from the MameDev depot so it is compatible with the MAME4all romset.
It works on iOS 10+ devices and can be compiled with Xcode 8+.