NextPlane - NextPlane offers cloud-based, scalable unified communications federation service for the enterprise.
Yac - Take your time back from Zoom & Slack
Voxer - Turn your phone into a Walkie Talkie. Don't waste time on phone calls and voicemails.
Beseda - Async video and audio messaging for remote teams
Sameroom - Chat interoperability-as-a-service
SuperNormal - Async video updates for remote teams