Apps Related to Instant Messaging

QuteCom, formerly WengoPhone, was a free and open-source VoIP client supporting the SIP protocol. It enabled users to make voice and video calls, send instant messages, and connect with contacts across various networks, including Google Talk.

Spark is a free, open-source instant messaging client optimized for businesses and organizations. It integrates seamlessly with Openfire servers and supports a wide range of features including group chat, file transfers, and screen sharing, making it a versatile communication tool.

Digsby was a multi-protocol instant messaging client that unified connections to various chat networks and social media platforms. It allowed users to manage their conversations and updates from services like Aim, Msn, Yahoo, Twitter, Facebook, and Myspace all within a single, integrated application.