A college of mine has implemented iOS in-app purchasing on a auto-renewing monthly basis. I am taking over the code base and want to test it is working. I know the purchasing
There is no notification. You keep track of it yourself (the duration). You get a receipt with the original transaction that you save. Use this to verify (perhaps on launch each time) that the user's subscription is still active.
No notification will be generated by apple. You have to save the recipes on server or device by using nsuserdefaults or keychain. you have to track the duration by yourself.By caluclating Compare the product identifier in question to the product identifier of each in-app purchase receipt. If there is a receipt that matches, validation succeeds. Otherwise, validation fails.
When validation succeeds, your application enables the purchased functionality—for example, by downloading content or adding features. When validation fails, your application simply does not enable the functionality.
In the iTunes development guide, there's list of how long auto-renew subscriptions last in sandbox mode:
Sandbox Testing Your In-App Purchases
You are required to test your in-app purchases in a sandbox environment before you submit them for review by Apple. You must first sign out of your iTunes Store account from your test device Settings before attempting to use the sandbox environment. If you mistakenly use your test-user-account credentials to log in to a production environment on your test device (instead of in to your test environment), your account credentials become invalid and cannot be used as a test account again. For more details on how to avoid mistakes during test account use, see “Using Test User Accounts.”
When testing auto-renewable in-app purchase subscriptions in the sandbox environment, the duration times will be compressed to allow for more streamlined testing. Additionally, a sandbox subscription will only auto-renew a maximum of 6 times. After the subscription has auto-renewed 6 times, it will no longer renew in the sandbox. The compressed duration times are as follows:
Actual duration Sandbox duration
1 week 3 minutes
1 month 5 minutes
2 months 10 minutes
3 months 15 minutes
6 months 30 minutes
1 year 1 hour