Running Apps Directly on Android Wear
In chapters 2 and 3, we learned to build notifications on handheld apps and customize them for wearables. These notifications were issued in a handheld app and automatically shared with a paired wearable device. While notifications constitute an essential part of Android Wear, more involved applications require writing code that runs directly on a watch. Apps that run directly on Android Wear are powerful because they let you leverage most of the features of the Android SDK. For instance, you can build your own activities and services just as you would with a handheld app.