Reading other questions and searching on the web, I am clearly missing something very obvious.
I am trying to make an app preview video for iOS. I've followed Creating Videos for App Previews to record a video on my iPhone 13. This gives me a video with a resolution of 2532 x 1170 (as expected).
The App preview specifications states that the native iPhone 13 resolution is 2436 x 1125 and that the accepted resolution is 1920 x 886.
Why is the app preview specification native resolution different from the actual iPhone 13 resolution? Am I missing some insets?
When I use Quick Time to save my video as 1080p then I get an output resolution of 1920 x 888 (it seems to be rounding up since the perfect scale would have been 1920 x 887,2037915).
I am unable to see how I can get to the accepted native resolution of 2436 x 1125 or how I can resample it to 1920 x 886.
I get the exact same results using the simulator.
How do I create a preview video in the accepted resolutions?
OK, I knew I was missing something stupid: I should not be using iPhone 13 Pro for the video, but an iPhone 13 Pro Max. That gives the correct resolution.
Bonus tip: Make use of iMovie's built-in support for generating app previews (yes, I know this should be obvious, but just in case). This did allow me to record my video on my iPhone 13 Pro and still save it in the correct resolution.