Will it work on your TV?
The phone side (aircon, lights, the house guide, dinner picks) works with any TV. Only the TV screen and the TV buttons depend on the brand.
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No match for that. Open your TV's Settings, System, About (or Device Preferences, About): if it says Android TV OS, it is a Google TV or Android TV and works. Otherwise, ask on GitHub.
Want everything on a TV that is not Google TV or Android TV? Plug in a Google TV box (Google TV Streamer, Chromecast with Google TV, Onn) and set Guest TV up on that: the home screen, the Guest profile picker and Spotify search, on any TV with an HDMI port.
From the table in Guest TV's README, . Beta means the path is built from the maker's own documentation and couch-tv's work, and first reports from real TVs are wanted.