Sony
Works locally Bravia TVs with Google TV or Android TV.
A Bravia shows a code on screen the first time; type it in the app and it is done. After that the app names what is on, TV, YouTube or Netflix, rather than the code a Sony reports to the network.
LG
Works locally webOS smart TVs.
An LG asks once whether to allow the hub; press OK on its own remote and that is it. Its apps and HDMI inputs then come up as tiles to tap.
Samsung
Works locally Tizen smart TVs from 2016 on.
A Samsung asks you to choose Allow the first time. From then on the hub sends its buttons over your network, volume, arrows and sources, with no Samsung account needed.
Philips
Works locally Philips TVs with Android TV or Google TV.
A Philips shows a code to type in once. Then its apps and inputs are tiles on every phone, next to the TV in the other room, whoever made that one.
Google TV and Android TV
Works locally TVs and boxes that run them, including TCL TVs, the Google TV Streamer, Chromecast with Google TV and NVIDIA SHIELD.
Type the 6-character code the TV shows, and YouTube, Netflix, Prime Video and Disney+ open from tiles in the app, with nothing to set up on the TV.
Roku
Works locally Roku streaming sticks and players, and Roku TVs.
Nothing to do on the Roku itself: the hub finds it on your network and you confirm. Its channels appear as tiles, and play and pause work from any phone.
Apple TV
Works locally Apple TV 4K and Apple TV HD.
The Apple TV shows a code to type in once. From then on the app works its menu, play and pause and volume, so the box answers every phone in the house, Android ones included.