Android is hot, and many people are developing Android applications (apps for short). Perhaps you too would like to develop apps but are unsure about how to get started. Although you could study Google’s online Android Developer’s Guide ( http://developer.android.com/index.html ) to acquire the needed knowledge, you might be overwhelmed by the guide’s vast amount of information. In contrast, this chapter presents just enough theory to help you grasp the basics. Following this theory are recipes that teach you how to develop apps and prepare them for publication on Google Play ( https://play.google.com/store ).