Neil Brown on Nostr: If it helps, I've used A&A VoIP with:<li>GroundWire (iOS; they might have an Android ...

If it helps, I've used A&A VoIP with:<li>GroundWire (iOS; they might have an Android version now but I haven't tested it)</li><li>LinPhone (Android)</li><li>Blink (Linux, macOS)</li>

but mostly I route it through our FireBrick.