OnePlus is pushing a stable update of OxygenOS 5.1.0 today to the OnePlus 5 and 5T that brings each phone up to Android 8.1. The update includes full-screen gesture support on the 5T as well, similar to those seen on the iPhone X.
For those on the OnePlus stable track, the update will roll out incrementally over the coming days, so don’t be surprised if you don’t see it right away. Your best bet is to keep checking each morning to see if your phone has made the cut. Head into Settings>System updates to check.
The update includes the April security patch, new optimizations in gaming mode, a network boost, category tags in the app drawer, and auto names for folders based on category. It’s a decent little update.