Videoconferencing software that uses Qt

Kopete was a multi-protocol, free software instant messaging client released as part of the KDE Software Compilation. Although it can run in numerous environments, it was designed for and integrates with the KDE Plasma Workspaces. Kopete was started because ICQ blocked Licq from their network in 2001. According to the original author, Duncan Mac-Vicar Prett, the name comes from the Chilean Spanish word copete, meaning "a drink with your friends". Kopete has been nominated for multiple awards. The designated successor is KDE Telepathy from the KDE RTCC Initiative.

QuteCom (previously called WengoPhone) was a free-software SIP-compliant VoIP client developed by the QuteCom (previously OpenWengo) community under the GPL-2.0-or-later license. It allows users to speak to other users of SIP-compliant VoIP software at no cost. It also allows users to call landlines and cell phones, send SMS and make video calls. None of these functions are tied to a particular provider, allowing users to choose among any SIP provider.