watchOS will need to be updated with the new Unicode. Which I'm actually surprised there hasn't been a single word about any developer 2.1 betas or even a 2.0.1 at all yet. 9.1 is right around the corner (probably as soon as next week) because the new beta 4 for 9.1 the build number suggests it's the GM (on top the release notes have been updated and don't mention it as beta.)