Respected authority,
By looking at the job requirements, it shows that you need an IOS developer who do have know how about VPN and he should have worked with it. Well I am an IOS developer with 3+ years of experience. My recent app was "Personal training coach" for android and IOS. I have worked with 10+ cloud based apps. I have worked with complex UI by giving them flexibility to change them in future.
Moving forward, I can dedicate 30 hours per week and number of my working hours are negotiable. Feel free to ask anything.
Regards.