I have always thought of Java as a way of coding and an ecosystem, not just a language and virtual machine. When you code in Java you are part of a mature culture with amazing tools and expertise. When I joined the webOS team nearly two years ago I knew HTML and CSS very well, but very little JavaScript. Over time I have become pretty good at JavaScript but my newfound knowledge still can’t compare to my fifteen years of mad Java skillz. With Java, and the mature Java tools, I can knock out code in half the time. I didn’t want to give up my existing skills to play in the new world of smart devices.

I know I am not the only Java developer facing the job of building cross-platform mobile apps. The Java ecosystem is so big that any solution for using Java in new ways can be immediately used by millions of hard working developers. So I began to research the available options and found GWT and PhoneGap, two brilliant open source projects that let us take Java to new and exciting places. My research turned into a few prototypes, then a few developer talks, a webcast, and finally the book you are reading now.

Even before I began to write I knew I wanted to create a book that was both very hands on and also very short. We are busy people who need tools that work now. We don’t have time to spend learning the framework of the week. That meant I had to leave a lot out. GWT is a mature but still growing technology. To truly cover GWT itself would require an entire 500-page book unto itself. To even cover the mobile parts would be beyond what this text could cover. So I decided to focus just on what you need to get started and be productive right away. After reading this book you will be ready to build your own apps and, if you desire, jump into the rich world of third party libraries and tools. The last chapter lists a few to help you get started.