This book is written in a friendly way, and take you from the most basic concepts to finally get some significant knowledge of how to make some cool applications. I know some Java and knew nothing about XML, at the end when you finish with this book you get the nerve to face some code and not running away like if you had seen the worst nightmare turned to truth. Really you could learn to develop some basic and interesting applications, and the author teach you right from the scratch, explaining what every single word and/or instruction is doing in your code, what its awesome if don't have a lot of background related to programming. If you have at least some basic knowledge about OOP and Java that it's a bonus but not necessary, anyway you should learn 'em both in some point from here to some time soon. There're some minor errors but if you're into the context you easily pick'em up and all the apps are set up to run on the Android 1.5 Android Virtual Device. I just got some trouble with the video app, but I guess it's due to the external resource provided by the book. I'm not sure if the next books proposed by the series are in the same vein, I hope so. Excellent book!