The competition isn't going to happen at the end-developer level. Few game developers are actually going to be touching Metal directly. The competition is goin

The competition isn't going to happen at the end-developer level. Few game developers are actually going to be touching Metal directly. The competition is going to exist in middleware. Unreal, Unity, etc, will have Metal-optimized implementations on iOS, because they're still a big market. The real threat to OpenGL is if the Metal implementation on these engines is so substantially more powerful than the OpenGL implementation, and results in better-looking games or games running on cheaper/slower hardware.