Android TV Design Guidelines
The Android TV platform user interface provides the launch pad for your app's big screen experience. It's important to understand how your app is presented in the main user interface and how your app can help users get to the content they want quickly.
A large screen UX
Due to the viewing distance of the TV, users may not be able to process as much information on TV as they would on a computer or mobile device. Limit the amount of text and reading on TV screens.
The home screen is the start of the user experience. It provides a rich and cinematic overview of apps and content, including search, recommendations, and access to settings.
See the Material Design Guidlines for more about designing the home screen.
Navigation, Focus and Selection
Users typically navigate TV devices using a directional pad (D-Pad). This type of controller limits movement to up, down, left, and right. As you design your app for TV, make sure your user interface has clear paths for two-axis navigation by aligning objects in lists and grids.
A key aspect of making your application work well with a D-pad controller is to make sure that there is always an object that is obviously in focus. Your app must clearly indicate what object is focused, so users can easily see what action they can take. Use scale, shadow brightness, opacity, animation or a combination of these attributes to help users see a focused object.
Read more about designing navigation on a TV screen.