(The second version of the high-definition e-book PDF download of the Android platform development journey covers Android 2.2/2.3/2.4 from the perspective of the content owner, covers mobile phones and tablet devices, has rich cases, touches various mainstream uses, and introduces new features of the platform in depth. The journey of Android platform development is based on practice and introduces the basic concept, practical technology and use mode of Android platform development. The main contents include the use of program framework, high-end interface, database use, network communication and WEB development, wireless communication, multimedia use, personal information management, telephone system management, XML use, map use, etc. There are 95 cases included. If you have some experience in mobile platform development, you will soon learn the contents of this book. This document includes the following annexes:)