When enabled, your iPhone will detect if its camera lens is smudged, and your device will tell you to clean it to improve your image quality. It's a nice way to make sure you always get a good picture ...
If you don't have enough iCloud storage, it's easier to upgrade your cloud than get a new phone. In the US, you can upgrade to 50GB for only a dollar a month, or you can go bigger: 200GB for $3 a ...