[mk3]

I'm not sure about the timeline who released first, but there is popcorn chat app which allows to chat with people who are within one mile from you it was featured here a while back. The functionality seems to be the same less or more.

[mengto]

Hmm, popcorn is a single chatroom within a location. Ripple is multiple chatrooms within a location, but based on a topic. There is no signup. That actually creates some really interesting use cases. Hopefully, you'll decide to try it out! :)