Welcome to Training for Android developers. Here you'll find sets of lessons within classes that describe how to accomplish a specific task with code samples you can re-use in your app. Classes are organized into several groups you can see at the top-level of the left navigation.
This first group, Getting Started, teaches you the bare essentials for Android app development. If you're a new Android app developer, you should complete each of these classes in order.
If you prefer to learn through interactive video training, check out this trailer for a course about the fundamentals of Android development.
Online video courses
If you prefer to learn through interactive video training, check out these free courses.