The Vox Mobile app uses the same voice codecs than anyone else.
The default codec is SILK, which is made by ... Skype.
The optional codec is G.729, but you have to register to get it.
So, we have an app that is made from an Open Source template (CSIPSimple), the same that everyone else uses, and that uses the same codecs than anyone else.
Pervasip's self-proclaimed "unique technology" is nowhere in sight.
The only originality is in the plans.