CADisableMinimumFrameDurationOnPhone
A Boolean value that allows your app to access frame rates higher than the system’s default.
Discussion
Devices with ProMotion displays allow apps to dynamically request a frame rate they prefer. If you set this key to YES, your app can request any frame rate the display supports. If you set this key to NO, frame rates higher than the system default are unavailable.
For more information on refresh rates, see Optimizing iPhone and iPad apps to support ProMotion displays.