On an iPad Pro 11-inch (M4) running iPadOS 27.0 (24A437), ScreenCaptureKit delivers a maximum of 60 frames per second when capturing the entire screen, even while an app is rendering at 120 fps (confirmed with the Metal Performance HUD).
What I tested:
- Default configuration: exactly 60 fps, with every frame timestamp spaced 16.67ms apart.
- Setting minimumFrameInterval to 1/120 and queueDepth to 8, both before starting the stream and through updateConfiguration after it started: the values are accepted and read back correctly, but delivery stays at exactly 60 fps.
- Smaller output sizes (1/4 and 1/8 of native resolution): still 60 fps.
- ReplayKit broadcast upload extension: also exactly 60 fps.
Also, minimumFrameInterval and queueDepth are documented as available on iOS/iPadOS 27, but the iOS 27 SDK marks them as unavailable.
Request: please allow ScreenCaptureKit to capture at the display's full refresh rate (up to 120 fps) on ProMotion devices when minimumFrameInterval asks for it, and make minimumFrameInterval available in the iOS SDK.