Your app code can follow the logic flow below to support your in-app items. The scope of each IAP Helper API is straightforward and most integrations follow a similar logic flow, which is linear with a few branches. After item purchases, IAP Server APIs are typically called to verify purchases.
Purchased consumable items not reported as consumed cannot be repurchased.
You must call getOwnedList() whenever launching the application in order to check for unconsumed items or subscription availability.