I try to develop simple game for iOS. And have little problem.
When i start my game on Linux, OSX, HTML and iPad2, i see that game works with different speed. On iPad2 objects are moving slower. On Linux, OSX, HTML game works with same speed. I dont understand why.
My game uses backbuffer with constant size 2732x2048. Then i scale backbuffer to framebuffer. And i update all objects in update method with speed * delta. Speed value is constant on all platforms.
Code is here