Free subscription trial in iOS Newsstand app

Question

Following iTunes Connect Developer Guide, when I create In-App purchase of type "Auto-renewable subscription" for my application, I can offer a free trial and set it duration: http://developer.apple.com/library/ios/documentation/LanguagesUtilities/Conceptual/iTunesConnect_Guide/13_ManagingIn-AppPurchases/ManagingIn-AppPurchases.html#//apple_ref/doc/uid/TP40011225-CH4-SW9

Reading this post: https://stackoverflow.com/a/17088975/2555979 , I assume, that if we try to verify the receipt, which was send to the user after he subscribed first time (ever) and got a free trial subscription, we can differentiate, is this user at trial subscription, or has he purchased it already, only by checking difference between expires_date and purchase_date, if durations of purchased and trial subscriptions are different, or by checking the original_transaction_id or original_purchase_date (if current transaction is not first, the subscription was renewed -> it's not trial already). If I'm wrong, please, let me know, because that's how I see the process in theory, not the practice (can't test that at the moment).

Anyway, the main question:

At some day, user installs my app and subscribes. He automatically gets some time of free trial subscription. He enjoys my app, everything is great, and he decides to be subscribed in future and automatically pay me every time when subscription ends. He doesn't even need to care about that, OK. Thanks to auto-renewable subscription mechanism.

After some time, he decides to stop auto-renew process. When last subscription expires, he don't pay me -> he is not subscribed from that moment. Okay.

But if, after some time, he decides to subscribe to my app again --- how about trial again? Who decides that? Is it in my responsibility to check, had he trial subscription or not? If yes, even if I know, that he had trial subscription already, how do I force him to pay from the first day of subscription, not after another trial period?

Answer 1

If he's using the same Apple ID, and you are selling the same subscription product, he will not get any more trial. Trials on subscription can only happen once regardless if they've stopped and resumed their subscriptions.

I know Apple's documentation has been very sparse on Newsstand. I have also experienced the same pain. I don't have any Apple documentations to back my answer up, but from my experience this is what happens. Customers will only receive a one time trial for every unique renewable product.