OpenGL is fully supported in MonoTouch, we distribute OpenTK with support for OpenGL ES 1 and ES 2, so it has a good binding that you can use in managed languages like C #.
, XnaTouch, , Cocos2D Monotouch-o-.
MonoTouch OpenGL XnaTouch Mono, , Unity3D. 3D- 2D- , Xna, .