How should an iOS app prevent consumable items from being reused?

Question

Probably a newbie question, I am using the Verify Store Receipts API to verify purchases of consumable items. How can I mark these items consumed so that the same receipt cannot be used again? Is there any option other than storing the used receipts?

Answer 1

Perhaps you could use a backend service to track receipts. Parse has brilliantly simple SDKs for iOS and Android that make it easy to persist bits of data to a provided server.