Asterisk is an open-source framework for building communications applications that turns an ordinary computer into a communications server. Asterisk powers IP PBX systems, VoIP gateways, conference servers, and other custom solutions.
Linphone is an open-source voice-over IP softphone, SIP client, and service. It may be used for direct audio and video calls through any VoIP Softswitch or IP-PBX.
CallHippo is an Intelligent cloud-based virtual phone system for small businesses & enterprises that comes with a power dialer, automatic call distribution, and more.
Dialpad is an AI-powered cloud communication platform that connects your teams through voice, video, messages, and online meetings.