I recently learned that it’s possible adjust the speed property of CALayer objects to slow down (or speed up) the animations on that layer and all its sublayers. Applying it to an app’s window will slow down every animation.
// Slows down all animations to 10% of regular speed! [[[UIApplication sharedApplication] windows] firstObject].layer.speed = 0.1;
It’s also possible to pause the debugger and set the speed from there:
(lldb) p [(CALayer *)[[[[UIApplication sharedApplication] windows] objectAtIndex:0] layer] setSpeed:2.0f]
The iOS simulator has an option in the Debug menu to slow down animations too but only speed will help you when testing with real devices.
Stack Overflow: Toggle slow animation while debugging with iOS Device
Photo Credit: Thomas Edwards
rob maceachern 