I'm developing a Newsstand app which uses in-app purchases and auto-renewable subscriptions to unlock and display paid issues of a magazine.
I have access to the database of the magazine's print subscribers and mechanism to identify each one of them with a unique code. I would like to allow people with the code to download digital issues they have subscribed to in print for free. However, I am worried that my app will get rejected from the App Store.
Quote the App Store Review Guidelines:
11.1 Apps that unlock or enable additional features or functionality with mechanisms other than the App Store will be rejected
11.2 Apps utilizing a system other than the In-App Purchase API (IAP) to purchase content, functionality, or services in an App will be rejected
Is allowing print subscribers to download issues they've already paid for a 'mechanism other than the App Store' or a 'system other than IAP'? Is there a best practice to accomplish this without violating the Guidelines? Has anybody solved a similar problem to this?
You should be fine unless you allow these users to register for said code inside your app. That means that you are circumventing in-app purchases and still using iOS to deliver content.
Say you have your own subscription service and people can purchase a subscription through your website. You are within your rights to allow them access to this subscription in the App.
What you are not allowed to do is allow them to purchase a subscription via your website in the App. In this scenario you must use In-App purchases.