Use this command to add any product IDs into the list e.g. com.yourcompany.yourproduct.iap. The first product ID you add becomes 0, the second is 1 etc. You must also specify the type of product this is, non-consumable(0), consumable(0), or subscription(2). Previously consumable products were added as type=1 but they are now added as type=0 and InAppPurchaseResetPurchase is used to reset a consumable to a purchasable state.
Consumable products are like coins that can be bought again and again, whereas non-consumable products are one off purchases like unlocking the full version of an app. In Google Play consumable and non-consumable products are added the same way. Currently this command is only supported on iOS, Google Play, and Amazon. This must be called before InAppPurchaseSetup, after that no further products can be added.
InAppPurchaseAddProductID ( szID, type )