The Leanback library makes it easy for media apps to add support for TV in a consistent and elegant interface. It is also easy to extend for custom features and interfaces.
This may seem like a lot of stuff and it may be hard to get started. Developers can now begin with the Leanback Showcase project, which has recently been made open source. This project contains examples of how to display cards, details, music and video playback, settings, dialogs, and custom fragments.
You can take a look at the project on GitHub and download it yourself to start building your own music or video TV app.