Hello,
I have 5+ yrs of experienced in android development and 3 yrs of experience in working with VOIP application, i have worked with almost all open source voip libraries, linphone, CSipSimple, Sip Droid, IMS Droid, antisip, Also have good experience in using c2call SDK for voip application.
Once i build linphone i will give you test build which you can test on your server, once you fine with it then we will work ahead for other changes.
I can do this task for you, also will provide long term support as well.
Please consider me for this job,
Thanks,
Best Regards,
PyDroidDev