In this book, I'll be creating an Android app from ground using Kotlin as the main language. The idea is to learn the language by example, instead of following a typical structure. I'll be stopping to explain the most interesting concepts and ideas about Kotlin, comparing it with Java 7. This way, you can see what the differences are and which parts of the language will help you speed up your work.

This book is not meant to be a language reference, but a tool for Android developers to learn Kotlin and be able to continue with their own projects by themselves. I'll be solving many of the typical problems we have to face in our daily lives by making use of the language expressiveness and some other really interesting tools and libraries.

The book is very practical, so it is recommended to follow the examples and the code in front of a computer and try everything it's suggested. You could, however, take a first read to get a broad idea and then dive into practice.

As you could read in previous pages (and probably the site were you downloaded), this is a lean publication. This means that the book is written and progresses with you. I'll continually write new content and review the existing based on your comments and your suggestions. In the end, it will also be your book. I want this book to be the perfect tool for Android developers, and as such, all the help and ideas will be welcomed.

Thanks for becoming part of this exciting project.