Apple on Monday seeded a fourth iOS 10.1 beta to registered developers, as well as the general public — potentially the final beta before the update is officially released.
Developers already on the 10.1 track can download the new beta as an over-the-air update. Otherwise, they'll have to go to Apple's developer portal to download it. Everyone else must be registered with Apple's Beta Software Program.
It's not clear what changes are in the new code, but Apple is likely extremely close to finishing the update, since it rarely issues more than four betas for a point release, if that many.
The main feature, though, will be a promised Portrait mode for the iPhone 7 Plus. The technology takes advantage of the Plus' twin cameras, identifying a subject then artificially blurring the background to simulate bokeh.