Squares Ahoy! A set of schematics have leaked online, which reinforce that the next iPhones will have a huge square rear-facing camera housing akin to the Huawei Mate 20 Pro.
https://www.notebookcheck.net/Leaked-schematics-confirm-that-2019-iPhones-will-have-a-square-camera-hump.415279.0.html