Can my guest use RINGR desktop in their browser while I use the iOS or Android app?

Yes, both you and your guest can connection to the conversation in any of our apps: RINGR Mobile Android, RINGR Mobile iOS and RINGR Desktop in either Firefox or Chrome. We hope to add support for the MS Edge and Safari browsers soon (although for Safari we are waiting for some missing WebRTC features to be added to the browser before we can support it).