Cross-Platform In-App Subscription Management Service

I've been trying to find a service that allows a business, such as one that I work for, manage in app purchases (mainly for subscriptions). It would be great if this was done cross-platform and not just on the web. Most services like Recurly or Chargebee only seem to be tailored for the web or if you want to purchase physical goods or services outside the context of an app (like Uber). How do magazine, gaming, or any other company types that leverage or rely on in-app purchases or subscriptions manage this data (Especially if they are building cross-platform products)?