I developed a OpenGL ES game several years ago and works well until now: I have downloaded Xcode 6 and iOS 8 in my iPad 3, and touch control (touchesBegan, touchesMoved, touchesEnded) only detect a square of 768x768 points, instead of 1024x768.
A margin of 256 points (1024-768) not respond to pulsations.
The game is in landscape mode.
It seems as if the touch control think that iPad is in portrait mode instead of landscape mode. Visually it is in landscape.
Looks like a bug in iOS 8.