Building a WatchKit App
It’s finally time to start building a real-world WatchKit application. As I said in Chapter 1, writing a WatchKit application really means creating an extension to an existing iPhone application. To make your WatchKit application useful, you need to find a way to present the information that your iOS application works with on the Apple Watch, where you have restricted screen space and are limited to interactions that can take place in the time between the user opening your application and lowering his arm—most likely just a few seconds.
Before starting work on your WatchKit app, take some time to decide what it can usefully do and consider how to present the available information in such a way that the user ...