- Free Personal • Proprietary
- Windows Phone
Zoiper IAX & SIP multilanguage and multiplatform (Windows, Linux and Mac OS X) softphone is a VoIP soft client, meant to work with any IP-based communications systems and infrastructure.
- Freemium • Open Source
Telephone allows you to make phone calls over the Internet or your company network. If your phone line supports SIP protocol, you can use it on your Mac instead of a physical phone anywhere you have a decent network connection.
- Paid • Proprietary
Acrobits Softphone, an app for entry into the world of SIP.