Linphone

High Quality Content by WIKIPEDIA articles! Linphone is a VoIP application available on PCs running Linux or Windows, Apple computers running Mac OS X, and Android and iPhone mobile phones. It uses the Session Initiation Protocol for communication and is licensed under the GNU General Public License. Linphone uses GTK+ for GUI and on Linux it can be also run as a console-mode application. It is compatible with telephony by using an Internet telephony service provider.