Apple on Thursday issued the first public betas of iOS 9.3 and OS X 10.11.4, following up on developer betas released earlier in the week. [Updated]
iOS 9.3 introduced a number of new features, such as a Night Shift mode for reduced eye strain, individually encrypted notes, and extra 3D Touch actions. People can also pair multiple Apple Watches with a single iPhone.
OS X 10.11.4 includes developer-oriented improvements to Safari, Live Photos support in Messages, and the same Notes security found in iOS 9.3.
As both updates are relatively early into testing, they're unlikely to be officially released any time soon. Apple has yet to even finalize iOS 9.2.1, which is much smaller in scope than 9.3.
Update: Developers should have access to iOS 9.3 beta 1.1, which fixes some early installation problems.