Kevin Purdy, one of my fellow writers over at Lifehacker and all-around good guy, has just published an excellent book covering everything you could ever want to know about Android—and it’s available online for free.
You can read the entire book from the Complete Guides web site, or if you feel like spending a few dollars to help Kevin buy me that beer he owes me, you can grab yourself an offline copy of the book in either paperback or PDF format from the Complete Android Guide web site.
What’s really interesting about this book is not just that it’s available for free, but it’s actually in Wiki form—so you, or anybody, can sign up and help edit future editions of the book. This means that this book will continue to update with new information as Android gains new features, which seems to happen every few months.
The Complete Android Guide [Online Book]
The Complete Android Guide [Paper / PDF Book]