Apple today released a handful of new beta versions of its core operating systems. These betas are specifically for developers, rather than public beta testers.
App writers can download and test beta 4 of iOS 10.2, watchOS 3.1.1, and macOS Sierra 10.12.2.
Previous beta releases of iOS 10.2 show the platform includes Unicode 9 with a fresh batch of emoji, as well as new wallpapers, iMessage screen effects, camera settings, video widgets, and emergency contact alerts. The newest beta of watchOS 3.1 includes stability improvements.
Apple typically makes the public beta available a day or two after the developer beta.