I can confirm that he is NOT crazy, this really did happen.
Here's the link to the iOS version (which is what I tried):
https://itunes.apple.com/us/app/team...577628510?mt=8
You can make side channels, so that people who are caving together can converse while others who are in town fiddling around can carry on casual conversations.
There's a "push to talk" mode and a "voice activation" mode (which was our preferred method).
It was fun and will come in handy during adventures.
During regular in-town screw-around stuff it might be too distracting... we'll see!
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