Rumour has it now that the iPhone 7 can record in 4K 60 fps. This is not a big surprise to me, but it's nice to see a rumour claim that's true.
https://tinhte.vn/threads/tren-tay-iphone-7-khong-hinh-khong-video.2639805/ (Vietnamese)
However, I would prefer if it can do it with h.265 HEVC, because h.264 AVC is getting long in the tooth. For 4K recording, h.264 takes up too much space, and h.265 would probably save about half the space (or around 40-60% according to this
article) at the same video quality.
Furthermore, we know that the iPhone 6 and later can already natively encode h.265 in hardware, so the technology is already there, albeit for lower resolutions. It just needs to be scaled up to 4K, and that support could very well be present in the Apple A10 two generations later.
By the same token, I'd love to see even 1080p video on the iPhone 7 / Plus have an HEVC option. I'd lose compatibility with these files on my iPad 2, but who cares? That's ancient. They'd probably be supported on my iPad Air 2 though (and the iPhone 6 and later).
In addition, I'd love to see 1080p h.265 support added for Live Photos, at a higher frame rate. Current 1080p h.264 Live Photos have too low a frame rate, probably because a higher frame rate using h.264 would increase the file sizes too much. I'm not as optimistic for this though, this time around.