OnePlus has just updated two of its recent releases, the OnePlus 5 and 5T, to support the latest version of Android 8.1 Oreo. It is part of the stable release of OxygenOS 5.1.0 and brings with it the April 2018 security patch, new optimizations for gaming mode, as well as network priority for a gaming app in the foreground. The phones’ launchers can now automatically name folders based on the category and include category tags in the search section.
The OnePlus 5T also now has navigation gesture support similar to what you can do with the iPhone X. You can enable this feature by heading into settings and disabling the navigation bar. The gestures include swiping up from the middle to take you to the home screen, pausing for a second after swiping from the bottom to access recent apps, and swiping from left or right side to go back (this can be used interchangeably). If you forget these gestures. You can just toggle the navigation bar off again and have the phone remind you of the gestures.
Source: Android Authority