This chapter has given you a taste of what types of user interfaces you can make in WatchKit. You know about the main interface objects, and you’ve gotten some experience putting them into an app. The layouts have been fairly simple so far, so it’s time to get a bit more advanced. By far the best way to exert control over layout is to use groups. You’ll notice I’ve been using the word “container” a lot, and there’s good reason. Groups allow you to define hierarchies of objects and lay them out together. They’re some of the most powerful interface objects in WatchKit. We’ll explore them in detail in the next chapter.
See the Apple Watch Human Interface Guidelines at https://developer.apple.com/library/ios/documentation/UserExperience/Conceptual/WatchHumanInterfaceGuidelines/index.html ...