Hello, i'm very interested on your project!.
I'm a developer with 2+ years working with mobile (Android & iOS) apps, my main field are Virtual Reality and Augmented Reality Apps so, we can make this project really quick and focus on the customization.
I have my own Google Cardboard to test the app and the devices required, if you check my Freelancer profile i've already done project with Google Cardboard SDK with excellent results!.
I will wait for your email for more details, thanks!.