Apple has released watchOS 4.2 for Apple Watch, and tvOS 11.2 for Apple TV, several days after releasing iOS 11.2 update for iPhone and iPad. The software updates for Apple Watch and Apple TV include various bug fixes along with a few new features.
watchOS 4.2 for Apple Watch includes support for Apple Pay Cash, a feature which allows users to send and receive cash payments over Messages. To use Apple Pay Cash on Apple Watch, you must have an iPhone with iOS 11.2 as well.
tvOS 11.2 for Apple TV includes support for HDR and frame rate adjustment based on media content for Apple TV 4k models. tvOS 11.2 also includes a new Sports tab which will display scores and live sports broadcasts through ESPN.
Apple Watch users can download and install WatchOS 4.2 via the Settings section on their paired iPhone. You must use the paired iPhone to update watchOS system software.
Apple TV users can download and update to the latest version of tvOS via the Settings app on their Apple TV.
Meanwhile, iOS 11.2 update was also released recently and includes important bug fixes, and should be installed by all iPhone and iPad users running a prior iOS 11 version.
For Mac users, macOS High Sierra 10.13.2 appears to remain in beta development, though a security update was recently released to address a rather problematic security bug impacting High Sierra.