Chapter 1, Working with Xamarin.Android, allows us to create native Android apps with the strengths of C# and .NET. Using C#, we can develop native Android apps and at the same time have the ability to share code with other platforms.

Chapter 2, Showing Views and Handling Fragments, explores one of the most important parts of Android apps—the user interface, as it is the most visible part of an app. When creating apps for Android, there are numerous different ways available to create these interfaces.

Chapter 3, Managing App Data, consists of the program that almost all apps make use of to process data. Android provides many ways to manage data, each being different and useful for different purposes. Data can be stored in a file, a dictionary, or in a SQLite database.

Chapter 4, Presenting App Data, is only useful to a user if the user is able to view it. Android has several means to present data, the most common being some form of list or collection.

Chapter 5, Communicating with the Outside World, explains communication, which is possibly the most important part of interaction, both between humans and technology. Most Android devices are built with Cellular, Wi-Fi, Bluetooth, or NFC communication technologies.

Chapter 6, Using Background Tasks, is where the users expect mobile apps to be fluid, dynamic, and most of all, responsive. Long-running tasks, even those running for a few milliseconds, must be run in the background to keep an app responsive.

Chapter 7, Notifying Users, explains notifications, which draw the user's attention to let him/her know something has happened. Android apps can present notifications in several ways, ranging from a quick popup to a persistent message from a remote server.

Chapter 8, Interacting with Other Apps, explains that users have many apps installed on their Android devices. By developing apps to be aware of other apps, our apps can communicate and request data from these other apps.

Chapter 9, Presenting Multimedia, consists of an explanation of audio, video and photos, the most vivid means to convey information to the user. By making use of Android's many features, an app can present a user with dynamic images and sounds. This can be used to provide a function or enhance other functionality.

Chapter 10, Responding to the User, explicates that a user can interact with Android apps in many ways. The user can manipulate virtual objects using the device's touch screen, or trigger the sensors by moving the device in the physical world.

Chapter 11, Connecting to Wearables, is one of the newest things with regard to technology; it is the increase in wearable devices. Android Wear is a special version of Android that allows device manufacturers to create wearables and permit typical Android apps to run on them.

Chapter 12, Adding In-App Billing, elucidates Android app developers can capitalize on the fact that users are willing to pay for new or additional features in the app. This is especially the case with mobile games that support purchasing virtual products or subscriptions.

Chapter 13, Publishing Apps, posits that once an Android app has been created, the next step is to release it into the world. Google has created the Google Play store, which can be used to distribute mobile and wearable apps. Before distribution, mobile apps can be compressed and protected against malicious users.