Linphone - Linphone is an internet phone or Voice Over IP phone (VoIP).
We-Talk - Free online chat rooms where people chat and meet each other and chat with the stranger and learn new cultures and make friends.
Zoiper - Cross-platform VoIP softphone dialer for SIP and IAX systems
Phoner - Softphone for VoIP, CAPI und TAPI.
Sipdroid - Free and open-source SIP/VoIP Client
3CX Phone System - 3CXPhone is a free VoIP phone available for Windows, iPhone or any Android based smart phone such...