Camera
Seriously, just go and buy a full frame digital camera (Canon 6D) if you actually care about your photos. Any upgrades to the iPhone camera will be minor (especially for noise levels in low light, and you will never be able to achieve narrow depth of field with a phone).
Hopefully a bump to at least 10 mp.
We have been at 8 since the 4s.
Yes i would like to crop without losing too much detail
Seriously, just go and buy a full frame digital camera (Canon 6D) if you actually care about your photos. Any upgrades to the iPhone camera will be minor (especially for noise levels in low light, and you will never be able to achieve narrow depth of field with a phone).