Introduction
The previous chapter introduced you to the core elements of Android development, from configuring your app using the AndroidManifest.xml file, working with simple activities, and the Android resource structure, to building an app with build.gradle and running an app on a virtual device. In this chapter, you'll go further and learn how the Android system interacts with your app through the Android lifecycle, how you are notified of changes to your app's state, and how you can use the Android lifecycle to respond to these changes. You'll then progress to learning how to create user journeys through your app and how to share data between screens. You'll be introduced to different techniques to achieve these goals so that you'll be able to use them in your own apps and recognize them when you see them used in other apps.