Developed by devhub.io
Robust, ubiquitous and massively scalable Jabber / XMPP Instant Messaging platform
The most feature-rich Tox client; P2P instant messaging, audio and video calls.
SIP softphone for Mac
A full-featured implementation of Mumble for Android devices.
HOMER 5 - 100% Open-Source SIP / VoIP Packet Capture & Monitoring
Pentesting framework using Node.js powers. Specially focused in VoIP/UC.
The Open Source Cloud Communications Platform
The Original Free and Open Source Game Control Panel
SIPVicious suite is a set of tools that can be used to audit SIP based VoIP systems.
TeamTalk 5 Development
OpenSource VoIP Door-Intercomstation
An Android application that sends and receives SMS messages using a VoIP.ms account.