Developing Apple Watch apps is extremely frustrating and limited for one big reason: unlike on iOS, Apple doesn’t give app developers access to the same watchOS frameworks that they use on Apple Watch.
Instead, we’re only allowed to use WatchKit, a baby UI framework that would’ve seemed rudimentary to developers even in the 1990s. But unlike the iPhone’s web apps, WatchKit doesn’t appear to be a stopgap — it seems to be Apple’s long-term solution to third-party app development on the Apple Watch.