OnePlus did say that they will be offering the Android 7.0 Nougat to their OnePlus 3 users before 2016 ends and it looks like they are sort of sticking to their words with the release of the Android 7.0 Nougat Beta version for the OnePlus 3.
The beta version will not only bring in the new update but it will also come with a few new features and updates like the new notification design, new settings menu design, multi-window support, custom DPI support and more.
If you are a OnePlus 3 user and is interested in trying the beta version out, you will ned to download the update manually as it will not be released OTA. Since this is a beta version, you also need to understand that it might come with bugs and glitches as well.
The new Android 7.0 Nougat beta will not be offered to the OnePlus 3T so they will have to wait until next year to get a taste of the new Android 7.0.