We need an objective c wrapper for the open source PJSIP voip library. We can provide the .h interface files which specify the functions we require.
You will need to have experience woking with pjsip and objective c for IOS. If you have done voip apps for iphone, you will probably have these wrappers already done, therefore there shouldn't be too much work involved.
It would be ideal if you can provide working .xcode project for ios sdk7 with pjsip+object c wrappers+testing functions.
If you can do some of this, please contact us.
Please see the .h file attached for specifications.