When “allow display mode changes” is selected under the external display in iPad’s settings, Infuse does NOT match the frame rate and dynamic range of the content being streamed. Apple TV has similar settings that ensure the frame rate and dynamic range of the content match what is being displayed, and Infuse does match correctly there.
This means that when the iPad is connected to an external display, any content, whether 720/1080p or 4K at any frame rate is displayed at 4K@60Hz. Content is also forced to the dynamic range selected in the settings, so SDR and HDR content is displayed in Dolby Vision, if the recommended Dolby Vision setting is switched on (or HDR/DV content is displayed in SDR if SDR is selected).
The only app I’ve found so far that can reliably match the frame rate and dynamic range of the content is Youtube.
Could you kindly look into this?