The free app that came with my Firestick.
Which is not the same as youtube's TV streaming service, firestick will be a supported device later in 2019.
From youtubetv/google's website....
https://support.google.com/youtubetv/answer/7129767?hl=en&ref_topic=7071745#
Notice that Amazon Fire Stick is not listed as a supported device.
You can stream YouTube TV to your TV using:
- Chromecast devices. Note: If you're using a first generation Chromecast
- TVs with Chromecast built-in (e.g., Android TV)
- AirPlay for Apple TV
- Google Smart Displays
Our TV app is available on:
- Android TV
- All Vizio SmartCast TVs
- Samsung & LG smart TVs (2016 models and newer)
- HiSense TVs (models: MTK5658, MTK5659, MSD6586)
- Apple TV (4th generation) and Apple TV 4K
- Xbox One, Xbox One S, and Xbox One X
- Roku: All Roku TVs, Roku Ultra, Roku Streaming Stick+, Roku Streaming Stick (3800x, 3600x), Roku Express/Express+ (3910x, 3900x, 3710x, 3700x), Roku Premiere+, Roku Premiere, Roku 4, Roku 3 (4200x, 4230x), and Roku 2 (4210x).