Trillian is a proprietary multiprotocol instant messaging application. Developed by Cerulean Studios
License: Freemium
Jitsi is primarily focused on video conferencing and collaboration, making it ideal for online meetings, while Trillian is a multi-protocol instant messaging application with a strong emphasis on secure messaging and file sharing. Both have their unique strengths, with Jitsi being open-source and customizable, and Trillian offering cross-platform support and encryption.