Apple has released finished (that is, non-beta) versions of OS X 10.11.6, iOS 9.3.3, tvOS 9.2.2, and watchOS 2.2.2. All are basically maintenance releases with bug fixes and performance tweaks.
You can grab OS X 10.11.6 at the Updates section of the Mac App Store. iOS 9.3.3 can be downloaded as an over-the-air update or via iTunes. watchOS 2.2.2 can be downloaded and installed through the Apple Watch app on an iPhone. tvOS can be downloaded through the System section of the Settings app on an Apple TV.