Android is the world's favorite mobile operating system and B4A is the easiest rapid app development tool, allowing complete beginners to create powerful Android apps using the easily learned BASIC language. It is free and can be downloaded from https: //www.b4x.com/b4a.html. This book covers B4A version 12.50. It starts with step-by-step beginners' guides explaining how to plan, design, develop, test, publish and make money from Android apps in the shortest possible time. It explains how to use B4A to create graphics and databases, to communicate with the user and to modify your app dynamically so it will look good on a wide range of devices. It includes a comprehensive reference guide to the B4A user interface and language, providing lists, explanations and illustrations of every keyword, object and core library. This complete guide is suitable for intermediate and expert developers but will also be useful for beginners. It covers every aspect of B4A from installation and using the WYSIWYG visual editor through a comprehensive reference section to extending the tool using Additional Libraries supplied by other users. It will quickly repay its cost by the time saved in finding the information you need when you need it. What readers said about this book: "This was a book that I now use as a constant reference and have found it a mine of information." "Brilliantly written and presented." "Excellent book. Just what I was looking for." "I will not now be able to think of developing an app without this book at my side." About B4A B4A is widely recognized by professional developers as the simplest and most powerful Rapid App Development tool available for Android. For example they say: "I've [made] more progress with B4A in 3 hours than I have in 3 months with other Android IDEs." Morgan Matthews. "I must say as a Visual Basic expert B4A is the best software purchase I've made in a long time. Within an hour of installing I had a fully functional application running on both my phone and tablet."Dylan Palmer. "This is the greatest product ever! After spending two months trying to learn Java, I stumbled upon you. I have been a VB programmer for 25 years, and I am in heaven now! Thank you!" Marc Mieher. However it's not always easy to find the information you want from the on-line help. That's why developer Wyken Seagrave wrote this book. Because B4A is free, Penny Press will give 10% of the profit from the sale of this book to support the developer, Anywhere Softw