There are plenty of improvements even when you aren't headed for your morning run. There's a slew of new watch faces, including a Siri face that provides context-sensitive info, a trippy Kaleidoscope face and Toy Story characters. You can browse apps in a easier-to-tap list instead of the usual grid, and the music app has been reworked with both a fresher interface and automatic syncing for Apple Music playlists. You'll also find hooks for Apple Pay Cash, although the money transfer feature won't be available until later in the fall.

A heads-up: watchOS 4 won't be available for your Watch until you install iOS 11, so be sure to do that first.