Beta 4 of OS X El Capitan 10.11.4 for Mac, watchOS 2.2 for the Apple Watch, and tvOS 9.2 for the Apple TV 4 is out and available to download right now.
[ Continue reading this over at RedmondPie.com ]
Beta 4 [+]
El Capitan 10 [+]
Apple Watch [+]
Apple TV 4 [+]