So apple recurring payments (the ones like magazines) are really only allowed for things that grant monthly content. You can't do apps that have a service component like this through that payment scheme.

You can sell the app 1x with the service bundled in it, launch this as a website service that the apple app store just happens to have a client for (that has no way to take payment), or you can sell consumable credits the user can use in a pre-paid phone esque way to use the service, or lastly you can have a non-automatic way to do a subscription called a "non-renewing subscription" in which the person has to click every month to pay you.

I think you folks have some thinkin about how you're going to do this. Email me in my profile if you'd like to chat about this a bit, I do this for a living and have fought with apple about subscriptions for years for many clients