In this chapter, we learned how we can build a custom watch face by using Google's official API so that we can create our very own custom watch face service and custom watch face class to handle the presentation of a digital clock with date and time, as well as battery usage within the watch face layout.

Then we looked at how we can debug our wearable applications with Bluetooth that are running in the wearable device. Next, we spent some time learning about the design guidelines for Android wearable and the design considerations developers need to consider when designing their user interfaces, specifically to conserve battery power when running resource-intensive tasks.

In closing, we looked at the steps involved when packaging our wearable application so that it can be sent to users to be installed and used within the handheld mobile device.

In the next chapter, we will learn more about the data layer API and how we can synchronize data from the Android wearable with the handheld...