Jitsi (formerly SIP Communicator) is a free and open source multiplatform voice (VoIP), videoconferencing and instant messaging application. Developed by University of Strasbourg (France), plus many others.
License: Open Source
Conversations is a user-friendly messaging app with strong encryption and rich features, ideal for secure communication. Jitsi, on the other hand, is an open-source video conferencing tool that excels in high-quality video and audio, making it suitable for larger meetings and collaborations.