This one has stuff related to team collaboration and general communication between people
- Rocket.chat (Collaborative Chat platform)
- mattermost (Collaborative platform)
- Signal - Rock solid, tested and proven (https://whispersystems.org/)
- Simlar - Untested; Unaudited new kid on the block
- Kontalk - The network itself is run by the community; funded by donations (https://kontalk.org/)
- Rumble - Let's you communicate without a stable Internet connection (http://www.disruptedsystems.org/)
Lots of problems here since popular web-conferencing software have limited support for Linux and require obnoxious add-ons. Webex needs you to install Java Plugins. Other software require Adobe Flash. Very few support HTML5 / WebRTC or other open standards on modern browsers. Here are a few noteworthy mentions of Free Software alternatives to common webconferencing systems.
- WebRTC / HTML5
- BigBlueButton - (https://bigbluebutton.org) https://mozillaignite.org/apps/374/
- Apache OpenMeetings - (http://openmeetings.apache.org/)
- WebHuddle - (https://www.webhuddle.com/)
- MConf - A relatively new kid on the block based on BigBlueButton (http://mconf.org/)