Question

there are some apps that seem to recognize the iPhone’s iTunes user.
I need to develop an app that supports In-App Purchase of kind “Subscription”.
Apple wants that my app grants the subscription in every user’s device (iPhone, iPod, iPad).
To do so I can build a server-side subscription system that binds the subscription with a kind of just created user inside my server.
To do things better I suppose that if my app can know the iTunes user that subscribes my service on the iPhone, it can store it inside my server.
If the user download the app on an iPad too, my app can ask the server to understand if the current iPad user is the same that subscribed my service on the iPhone and, if so, can grant the service on the iPad too.
So, can my app know what iTunes user is subscribing my service (with an In-App Purchase)?

Thanks In Advance

Answer 1

The answer is:
I CANNOT!
so the only way to manage subscriptions on multiple devices is to build a kind of “subscription registration” that lets the user to register his/her subscription so he/she can login from another devices and restore the subscription.