Designing Web Content for watchOS - WWDC 2018 - Videos - Apple Developer
If you don’t fancy watching this video, Eric Runyon has written down the salient points about what it means for developers now that websites can be viewed on the Apple Watch. Basically, as long as you’re writing good, meaningful markup and you’ve got a sensible font stack, you’re all set.
Or, as Tim puts it:
When we build our sites in a way that allows people using less-capable devices, slower networks and other less than ideal circumstances, we end up better prepared for whatever crazy device or technology comes along next.