I'd love to see this feature request include all major non-proprietary protocols (SIP, XMPP) as well as an API (or similar) to integrate popular proprietary protocols (e.g. Skype, Viber, WhatsApp, appear.in, ...). Apart from voice calls it should also support video calls. (I'm not sure whether integrating messaging would also make sense.)
I'd love to see this feature request include all major non-proprietary protocols (SIP, XMPP) as well as an API (or similar) to integrate popular proprietary protocols (e.g. Skype, Viber, WhatsApp, appear.in, ...). Apart from voice calls it should also support video calls. (I'm not sure whether integrating messaging would also make sense.)