I have thought about this solution previously too. The main issue is, how do you solve the chicken and egg problem of getting critical mass for it to be useful?
Sidenote: Why did you pick the .ms sub-domain? It made me think of Microsoft, which obviously doesn't go with an iOS app.
It was the only one available that Google doesn't penalize or geotarget. I agree the Microsoft connotation is odd but if the project is a success we'll be able to acquire another domain.
Sidenote: Why did you pick the .ms sub-domain? It made me think of Microsoft, which obviously doesn't go with an iOS app.