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For a basic app with nonconsumable in-app purchases, has anyone figured out best practices for using SKPaymentQueue's restoreCompletedTransactions ? Observations I know it's recommended to always register a transaction observer to receive pending transactions that make their way back to the app, but this is a different question. It looks like restoreCompletedTransactions is something the app has to actively decide when to call to poll for all the purchases the customer has already made. From what I can tell, the method is designed to retrieve purchases that may have been lost. For example a customer might install or move an app to a new device in such a way where the user defaults (where Apple recommends recording nonconsumable payments) are lost or reset. Concerns What's not clear to me is how to automatically detect this condition (i.e. how to decide when to poll for missing purchases) in a reliable way. I don't want to screw this up and risk denying a c