Razer announced the Razer phone last year & since then the device has been updated randomly and Razer actually has kept improving the Camera as well. The latest addition in that improvement list is the addition of a Portrait Mode which Razer pushed with a 366.3 MB software update.
The secondary rear camera on the Razer phone has a 2x Telephoto lens which alongside zooming in, was also capable of talking Portrait shots. However, the software support for wasn’t there till now. The new update finally added support for Portrait shots.
The update also includes the May security patch & Razer reportedly fixed the touchscreen issues as well, which came alongside the initial 8.1 Oreo Update. You can now also lock recent apps to avoid accidental closures during swipes or using the Clear All option.