I don't really understand this idea. Do I have to provide a restore button for the user? What method should this method invoke? What will restore will do?
This question is related to
iphone
in-app-purchase
restore
You typically restore purchases with this code:
[[SKPaymentQueue defaultQueue] restoreCompletedTransactions];
It will reinvoke -paymentQueue:updatedTransactions on the observer(s) for the purchased items. This is useful for users who reinstall the app after deletion or install it on a different device.
Not all types of In-App purchases can be restored.
Is it as optional functionality.
If you won't provide it when user will try to purchase non-consumable product AppStore will restore old transaction. But your app will think that this is new transaction.
If you will provide restore mechanism then your purchase manager will see restored transaction.
If app should distinguish this options then you should provide functionality for restoring previously purchased products.
You will get rejection message from apple just because the product you have registered for inApp purchase might come under category Non-renewing subscriptions and consumable products. These type of products will not automatically renewable. you need to have explicit restore button in your application.
for other type of products it will automatically restore it.
Please read following text which will clear your concept about this :
Once a transaction has been processed and removed from the queue, your application normally never sees it again. However, if your application supports product types that must be restorable, you must include an interface that allows users to restore these purchases. This interface allows a user to add the product to other devices or, if the original device was wiped, to restore the transaction on the original device.
Store Kit provides built-in functionality to restore transactions for non-consumable products, auto-renewable subscriptions and free subscriptions. To restore transactions, your application calls the payment queue’s restoreCompletedTransactions method. The payment queue sends a request to the App Store to restore the transactions. In return, the App Store generates a new restore transaction for each transaction that was previously completed. The restore transaction object’s originalTransaction property holds a copy of the original transaction. Your application processes a restore transaction by retrieving the original transaction and using it to unlock the purchased content. After Store Kit restores all the previous transactions, it notifies the payment queue observers by calling their paymentQueueRestoreCompletedTransactionsFinished: method.
If the user attempts to purchase a restorable product (instead of using the restore interface you implemented), the application receives a regular transaction for that item, not a restore transaction. However, the user is not charged again for that product. Your application should treat these transactions identically to those of the original transaction. Non-renewing subscriptions and consumable products are not automatically restored by Store Kit. Non-renewing subscriptions must be restorable, however. To restore these products, you must record transactions on your own server when they are purchased and provide your own mechanism to restore those transactions to the user’s devices
Source: Stackoverflow.com