Popcorntime torrent streaming app makes its way, via open source to the Apple TV 4. Popcorntime allows you to watch in realtime, torrents. torrents are multi part, multi source file that you can watch as they download
There are two ways to side-load an app on ATV 4. It's either the long way by building with Apples xcode which is a lengthy multi step nightmare or by using a services that co-sign Apps so tha install 3rd party apps on the ATV. A service like iPwnStore is one such service i use to make it easy.
The two latest Apps to drop on iPwnStore are PopcornTime and an old School Game Emulator call MaMe.