As a hobbyist photographer that still likes using a nice phone camera, the thing that is most important to me is that the phone camera accurately reflects skin tones in photos of people. The only things I'm really photographing with my phone are snapshots of myself and my family and friends doing things together. For everything else I use a real camera. I think the current generation iPhones are pretty good at this and I don't really need it to get any better than it already is, if I want to take a serious photo I will go use a serious camera.