A good collection of recipes for Android developers is offered in this book. Each recipe specifies the minimum Android application programming interface (API) level needed; most are quite low, so these recipes will work on almost all current Android devices. Even though the book is not intended for those with no Android background, the first chapter does have useful recipes for installing and using Android from the command line and from Eclipse. This chapter also includes a complete example application for converting units. The sections in the remaining chapters have the code necessary to understand the related recipe, but do not include complete apps. This is in keeping with the intermediate nature of the content, which assumes that readers will be able to build apps using the recipes.

Chapter 2, “User Interface Recipes,” is the longest, with 25 recipes, including, for example, Monitoring Click Actions, which shows how to make a button work; Animating a View, which describes both the system animations included with the software development kit (SDK) and how to create custom animations; and Customizing Keyboard Actions, which shows how to customize the enter key and/or the action that occurs when it is tapped. Several chapters conclude with a section labeled Tools to Know. In chapter 2, for example, the highlighted tool is DroidDraw, which facilitates building user interfaces.

The next chapter, “Communications and Networking,” has 11 very useful recipes, including Accessing WebView with JavaScript, Accessing a REST API, Parsing XML, Receiving SMS, and Communicating Over Bluetooth. The techniques are clearly explained and are accompanied by the necessary Java code or Extensible Markup Language (XML) files. Chapter 4 features recipes for annotating maps, adding speech recognition, and creating a tilt monitor, among others. Each of these recipes might be useful in many contexts and referenced as needed. The chapter concludes with a section on the SensorSimulator tool, used for testing on the emulator. The chapter on persisting data starts with preferences, which allow the user to change the settings for an app, and continues with a section on working with files, and then with databases, concluding with a discussion of the SQLite3 tool.

The last two chapters show how to interact with the system and how to work with libraries. The book concludes with appendices on a scripting layer, the Android native development kit (NDK), and app design guidelines. It is a very useful resource for Android developers.