Recs.
Updated
Jami is an open source, decentralized, cross-platform, encrypted communication software allowing audio and video calls, messages, file transfers, media streaming and videoconferencing.
Specs
Pros
Pro Video conferences
Make audio and video calls with multiple people on Jami. Easily add new participants. Because Jami does not rely on servers, the conference is hosted by the device of the person who initiates it. It mixes the audio and video feeds from all the participants and sends it back to them so everyone can see and hear each other. For this reason, the maximum number of participants depends on the hosting device's computing power and available bandwidth. The developers have tested video conferencing with up to sixteen members; however, it could potentially go higher.
Pro Open development
The Jami software has many features and is stable; yet, the rate of development is increasing as more developers are contributing to provide even more features while keeping the software stable.
https://git.jami.net/
Pro Language support
Translated into many languages and open for more translations.
https://www.transifex.com/savoirfairelinux/jami/
Pro Screen sharing and media streaming
You can change the source of the video feed you send your friends during a call, allowing you to share either your entire screen or only sections. You can also stream any audio and video media files, allowing your friends to see or hear them without having to transfer them first. This is accessed by right-clicking on the screen during a call.
Cons
Con Chat history shared across devices
Con Group text chat
Not yet supported; however, group video conferences are supported.