Fire App Builder is a java framework that allows developers to quickly build immersive, java based Android media applications for Fire TV, without writing code. Fire App Builder accomplishes this by using a plug and play java framework with easy configuration files. Developers simply specify the format of their media feed in a json file and add resources for logos and colors to create a rich media TV experience quickly. Fire App Builder supports multiple modules for Analytics, Authentication and Advertising that you can enable for your app.
Full Documentation for Fire App Builder is located here.
Fire App Builder is java based and is built using Android Studio. If you would like to build web apps for Fire TV, please check out the Web App Starter Kit.