Developers are going to have a field day today; new betas for a number of Apple's operating systems and for Xcode were released in the Apple Developer Center.
iOS 9.3 beta was released today for iPhone, iPad and iPod touch. Apple notes that devices that are updated to iOS 9.3 cannot be restored to earlier versions. No information on what the beta or the final version of iOS 9.3 will contain has been released, but the ".1" releases often include new features and significant performance enhancements. Apparently one of the features of iOS 9.3 will be the ability to pair multiple Apple Watches with a single iOS device.
9to5Mac also reports that Apple is adding the ability for a single iPad to be shared with a number of students; that's most important in school settings, where multi-user support has been on the "want" list for educators for quite a long time. Apple's also launching a Classroom app for teachers, an Apple School Manager service, and the ability to create bulk Apple IDs. All of these features seem to be targeted at schools only; there's no word on whether multi-user support will become available to the general public.
Apple Configurator 2.2 beta, which is used to set up and deploy groups of iOS devices, also hit the developer center today.
For Apple Watch developers, the first beta of watchOS 2.2 was released as well, in addition to the initial beta of tvOS 9.2. Not wanting to overlook the desktop operating system, Apple also released OS X El Capitan 10.11.4 beta today.
And finally, Xcode 7.3 beta was also released. As with all beta software, unless you know what you're doing, don't install it.