I do not believe this will work for anything older than the galaxy watch 4, but I could be wrong. The Galaxy watch 4 was the first model to use Wear OS. The watch 3 still runs on Tizen OS.
I do not believe this will work for anything older than the galaxy watch 4, but I could be wrong. The Galaxy watch 4 was the first model to use Wear OS. The watch 3 still runs on Tizen OS.