OnePlus has started rolling out the dev preview of OxygenOS 4.0.1 to OnePlus 3 devices. The company has not updated the exact official change-catalog yet. The size of OxygenOS 4.0.1 dev preview is 36MB. As per the size, we guess it will have only bug fixes and performance improvement updates.
Earlier this month, after several beta tests, the company has started rolling out the final stable Nougat OTA based on OxygenOS 4.0 to OnePlus3 devices. Basically, OxygenOS 4.0 is based on Android 7.0 Nougat. The company has not posted OTA zip for the OxygenOS 4.0.1 dev preview yet but we are expecting it should be available shortly as the update rolls out to more users/developers.
We will keep you informed about the further updates. In case, if you are still running the Android 6.0.1 Marshmallow on your OnePlus 3 or 3T devices, you can download the Nougat based OxygenOS 4.0 full ROM zip for your OnePlus 3 or OnePlus 3T.