MicroSIP

Jitsi (previously SIP Communicator) is an audio/video and chat communicator that supports protocols such as SIP, XMPP/Jabber, AIM/ICQ, Windows Live, Yahoo! and many other useful features. Jitsi is...

Ekiga (formely known as GnomeMeeting) is an open source VoIP and video conferencing application for GNOME. Ekiga uses both the H.323 and SIP protocols. It supports many audio and video …

Linphone is an internet phone or Voice Over IP phone (VoIP). With linphone you can communicate freely with people over the internet, with voice, video, and text instant messaging. Linphone …

csipsimple will allow native sip for android device. It relies on the pjsip SIP stack and use the pjsip-jni project. The use of this native library will ensure a better …

SFLphone is a robust standards-compliant enterprise softphone, for desktop and embedded systems. It is designed to handle several hundreds of calls a day. SFLphone is available under the GNU GPL …

Telephone is a VoIP program which allows you to make phone calls over the internet. It can be used to call regular phones via any appropriate SIP provider, including Google …

Encrypted voice for Android. RedPhone provides end-to-end encryption for your calls, securing your conversations so that nobody can listen in. It's easy to use, and functions just like the normal …

Blink, a state of the art, easy to use SIP client. You can use it with any SIP provider or its own fully-featured SIP service. Voice over IP * HD …

Yate is a softswitch (concept of separating the network hardware from network software). It supports VoIP protocols: H.323, SIP, IAX1, IAX2, RTP. For the plain old telephony systems (PSTN) it …

Twinkle is a soft phone for your voice over IP communcations using the SIP protocol. You can use it for direct IP phone to IP phone communication or in a …

Homer is a free cross-platform SIP softphone with video support. It is able to communicate in peer-to-peer mode without any infrastructure in the network. But it also supports SIP servers …