My educational app is structured around courses. Users can subscribe for "unlimited" courses or a "single course".
The question is how best to implement the "single course" subscription -- so that the app knows which course is subscribed and also so that the user can change courses?
One approach would be to define a separate subscription IAP for each course. Then it's trivial for the app to know which course, and the user could upgrade/downgrade/crossgrade to a different course using the Manage Subscriptions UI.
The problem is that we already have a dozen courses and we're headed for dozens more. I'm afraid the Manage Subscriptions UI wasn't intended to handle a case where there are hundreds of subscription options.
The other approach would be to have only one "single course" subscription; then I'd need to manage the course info myself and there'd be no good crossgrade path for the user.
Am I thinking about this correctly? Are there other options besides the two mentioned?