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
Imo is a user-friendly messaging app with a focus on video calls and voice calling, catering primarily to personal use. In contrast, Jitsi is an open-source video conferencing tool that excels in larger meetings and offers extensive customization, making it more suitable for professional and tech-savvy users.