Apple has released the fourth betas for iOS 9.3.3, OS X 10.11.6 and tvOS 9.2.2 with bug fixes and stability improvements. There are no new noticeable feature updates in these releases.
If you are already running the third beta on your iOS device, Mac, simply check for updates in Settings > General > Software Update or Mac App Store > Updates tab, respectively. Alternatively, if you are a registered Apple Developer, you can download the full versions from Apple for a clean installation.
Apple released the developer betas for iOS 10, tvOS 10, macOS 10.12 Sierra and watchOS 3 the same day as it announced them at WWDC 2016. The new releases contain a lot of new features, especially for iPhone, iPad, and Apple Watch users. Major updates include the opening up of Messages, Siri, Maps and Phone apps in iOS 10 to developers, redesigned and 3D touch enhanced notification center and improved 3D touch support on home screen icons with widgets support. With watchOS 3, Apple Watch gets some major and much wanted updates – instant app launch, multitasking dock, background app refresh and new watch faces.
The updates will release this fall to the general public while public beta testing will start in July. iOS 9.3.3, OS X 10.11.6 and tvOS 9.2.2 will serve as maintenance releases with bug fixes and stability improvements until then.