OnePlus 3 has to get Android 7.1 Nougat's first Beta build in this month and first stable update by end of this year. Now, CM14 ROM for OnePlus 3 has been posted officially and can be installed. Modders over XDA Forum have also posted hands-on video of OnePlus 3 running
If you own an OnePlus 3 and want to get a taste of Android Nougat 7.0 on it, you are in luck. Modders over XDA Forum have succeeded in flashing Android Nougat based unofficial CM14 build on OnePlus 3.
You can read and watch changes and new features Android Nougat brings