Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
Twilio Video - Real-time video infrastructure and SDK
Slack - A messaging app for teams who see through the Earth!
Amazon Chime - Online meetings and video conferencing
Cisco Jabber - Cisco Jabber lets you access presence, instant messaging (IM), voice, video, voice messaging, desktop sharing, and conferencing.
100ms Live - Video and Live Streaming infra for a video-first world