Adium is an Open source multi-protocol instant messaging client for Mac OS X, supports MSN, Jabber, Yahoo! and other networks. Developed by Adium Team
License: Open Source
Adium is a powerful, open-source messaging client that excels in customization and multi-protocol support but is limited to macOS and lacks modern features. Disa, on the other hand, is a user-friendly messaging app for Android that integrates well with notifications and supports multiple messaging platforms, but it has fewer customization options and is not open-source.