Android Essentials is a no–frills, no–nonsense, code–centric run through the guts of application development on Google's Mobile OS. This book uses the development of a sample application to work through topics, focusing on giving developers the essential tools and examples required to make viable commercial applications work. Covering the entirety of the Android catalog in less than 150 pages is simply impossible. Instead, this book focuses on just four main topics: the application life cycle and OS integration, user interface, location–based services, and networking.