Playing around with this, seems I created a new channel/room/page called "raar" (https://coffeehouse.chat/raar), I wasn't expecting it to just let me create something that seems to be just there on the homepage as literally the second channel, without any signup or anything. It also seems to be a public thing. I opened the link on my phone and joined the call from there and it connected. However when I tried again it wouldn't connect
Just had my first actual proper call, with a guy in Turkey who seemed very nice, call worked really well. In part of the conversation he asked about what I was working on, and I missed the ability to send a link through the call - (though maybe that's a sign that my own domain could have a better name!)