Another review from Singapore adds a different perspective: "I only use this for YouTube and Netflix so it's ok. 4K quality not really, more like 1080p unless you plugged this in a truHD TV." This suggests that the tablet's internal display may not fully resolve 4K detail, and the true benefits of 4K resolution might only be visible when connected to an external 4K TV or monitor.
: The iPad will "downscale" the 4K video to fit its specific resolution while maintaining the sharpness and HDR color data. srkwikipad 4k movies work
: Many movies are edited and finished using a lower 2K resolution master. To output a 4K stream, advanced interpolation algorithms analyze the 2K frame and generate new pixels to fill out the 3840 x 2160 layout. While it looks noticeably sharper than standard HD, it lacks the fine detail of a native 4K master. Another review from Singapore adds a different perspective: