implementing the SIP functionality in IOS5

Question

I want to build an iPhone app which has the option to make calls over SIP (VoIP) but at this moment I have no idea how to start.

Does anyone have some information about

Answer 1

check this below link. You will get source code from there and can biuld for both device and simulator.

https://github.com/radif/SIPHON-SIP-Client-that-actually-compiles