OnePlus has confirmed that it is now in the process of rolling out an update to the OnePlus 3 and the OnePlus 3T. The update brings the operating system version on both devices up to OxygenOS 4.1.3, based on Android 7.1.1 (Nougat). The update is rolling out as an over-the-air update to both devices and OnePlus has confirmed that both updates are rolling out on an 'incremental' basis. Meaning, not everyone will get the update at the same time. In fact, OnePlus specifically state that the OTA will only be heading out to "a small percentage of users today" with the much wider rollout expected to occur over the course of the next few days.
In terms of the actual update, most of it seems to revolve around a number of general improvements and fixes. Two of the improvements mentioned in the changelog are directly relevant to the camera experience on the two devices. The first is a reduction in blur when taking images of moving items, and the second is better stability when recording video. There are also some connectivity improvements included as well, in particular for Wi-Fi and Bluetooth connections. While fixes come in the form of a patch for an Instagram swiping issue and a patch for a hardware button malfunction issue. In addition, the changelog notes that you should expect a number of general bug fixes, as well as general improvements to the system overall.
The only specific new feature mentioned in the changelog is the addition of 'expanded screenshots'. Although, this was a feature that had been expected to be rolled out with a previous update (OxygenOS 4.1.0) which arrived mid-way through March. So it is unclear what is different here. However, if you had yet to receive the expanded screenshot feature (the ability to take screenshots that vertically capture more than you see on the screen), they maybe you will receive it with this update. As is typical with these update from OnePlus now, the company is also keen to hear back from users on their experience with its updates in general. Which can be done by heading over to the OnePlus forums and filling in a brief survey.