If you're running Open Beta on your OnePlus 7T or 7T Pro you should check for updates as the company just started rolling out Open Beta 5. Owners of a OnePlus 7 and 7 Pro should also be getting a new version, Open Beta 15, which has essentially the same change log as the 7T update. The change log includes one-handed mode, a feature that was first added to the OnePlus 7 series in January. You can enable it from Settings > Buttons & Gestures > Quick Gestures. Some forum members are reporting that this feature is not actually available, but that's the purpose of these beta tests, to catch...
Source: https://www.gsmarena.com/oneplus_7t_7t_pro_open_beta_5_brings_onehanded_mode_easy_dark_mode_toggle-news-43744.php
