Not really one game but a set of related games.
GameTheory can be used to give a good strategy for playing poker assuming your opponents are competent. There are various online casinos that host poker games, and there are reputed to be a lot of bots playing in these casinos, but this is hard to verify as often casinos have a policy of not allowing bots. Given that, and the fact that anyone with a decent poker bot is presumably quietly running it on as many games as possible, it is hard to know whether GameTheory is actually used for poker bots, or if something else is.