Xiaomi has reportedly patented a phone with an outward-folding display which leaves its I/O contained within a strip down 1 side of this device. If that concept sounds familiar, it is because this form-factor has already been debuted by Huawei in its Mate X series. Xiaomi's new take on it exhibits at least 4 cameras.
https://www.notebookcheck.net/Xiaomi-allegedly-patents-what-looks-like-a-Mate-Xs-clone.469073.0.html