It's a very easy way of making a chat between everyone sharing a space. No registration needed. Just start up bitchat and you share a chat room with everyone. It could be used to share useful information for the event, for playing some kind of game or raffle, to meet people with shared interests, etc. Even to order some some drinks and food, ot request a song to the DJ... Those are just some ideas. I'm sure people will have better ones. 🫂