Tracking development of pjsip, the Open Source SIP, media, and NAT traversal stack/SDK/library for Android, iOS, Windows, Linux, MacOS, RTOS, embedded, and pretty much anything, any device.
Also check PJSIP Documentation site.
eok did manage to make the Nintendo DS-based SIP app from Samuel running on the iPod Touch!!
VoIP confirmed!!! « iPod Touch Mods
After Nintendo DS, here is another pjsip port along the lines of VoIP on Consumer Devices product line: internet telephony on the iPod Touch. It needs a hardware modification to make activate the microphone though, so definitely not for the faint of heart!
Here is where we talk about pjsip development in general, and maybe other stuff as well. For the project itself, please go to the main pjsip project website. or pjsip documentation.
PJSIP is backed by Teluu, which provides professional support, additional licensing options, and a network of qualified consultants.
pjsip blog 