First, Apple introduced new watch faces, there are more than 6 new:

Aside from watch faces, a new 3 apps came to Watch OS:

There is now a dedicated AppStore to the watch, so you can browse the store, see rating and reviews and most importantly – download apps directly from the watch.

Apple also added a new feature – Activity trends, to stay active for long term success!

Another health feature is Noise App, it will protect your hearing health when there are loud noises around you. Plus, there is now a dedicated app for Cycle tracking for woman.

Here is everything they showed! Enjoy!
