Is it true that for iPad and iPhone, using CADisplayLink must be for 60fps?

Question

In other words, can we choose to invoke the handler at 20 times per second, or at 45 times per second, or must it be 60 times per second?

I guess one way to simulate it will be to use the timestamp given to the handler to determine if it is "time for action yet" -- if not, simply return without doing anything?

Answer 1

You can use the frameInterval property to invoke the handler every 60/n frames, where n is a positive integer.

You can't invoke the handler 45 times per second, but the following values are possible: 60, 30, 20, 15, 12, ...