iOS IAP- need advice on premium version of app - ios

Question

I've followed a tutorial to create an IAP for my game. My goal is to have a "Remove Ads" button. Once the user gets this IAP, the remove ads button disappears, and ads stop showing. On future launches of the app this purchase is loaded automatically.
I've got the basics of this down, but here are my issues.
I've created a sandboxed user, and every time I start my app it's asking me to login to itunes. I'd figure it should really only be asking me to login when I'm deciding to purchase the app. Is this related to me being a sandboxed user?
I'm also restoring purchases on every app launch. This seems to be happening automatically without login.. so why is it me asking to login every time? Should I be utilizing NSUserDefaults to avoid restoring purchases in the future?
Here is my code so far:
override func viewDidLoad() {
// storekit delegation
SKPaymentQueue.defaultQueue().addTransactionObserver(self)
SKPaymentQueue.defaultQueue().restoreCompletedTransactions()
self.getProductInfo()
}
func getProductInfo(){
if SKPaymentQueue.canMakePayments() {
let request = SKProductsRequest(productIdentifiers: NSSet(object: self.productID))
request.delegate = self
request.start()
}
// else {
// please enable in app purchases
// }
}
Delegate methods
func productsRequest(request: SKProductsRequest!, didReceiveResponse response: SKProductsResponse!) {
var products = response.products
if products.count != 0 {
self.product = products[0] as? SKProduct
}
}
func paymentQueueRestoreCompletedTransactionsFinished(queue: SKPaymentQueue!) {
if queue.transactions.count != 0 {
if let purchase = queue.transactions[0] as? SKPaymentTransaction {
if purchase.payment.productIdentifier == self.productID {
println("you bought it already")
}
}
}
}
func paymentQueue(queue: SKPaymentQueue!, updatedTransactions transactions: [AnyObject]!) {
for transaction in transactions as [SKPaymentTransaction] {
switch transaction.transactionState {
case SKPaymentTransactionState.Purchased:
// self.unlockFeature()
SKPaymentQueue.defaultQueue().finishTransaction(transaction)
case SKPaymentTransactionState.Failed:
SKPaymentQueue.defaultQueue().finishTransaction(transaction)
default:
break
}
}
}
Is this the correct approach?

Answer 1

1) Yes, the login requests are related to the sandbox user
2) You should be checking the receipt each time, not restoring purchases or storing separate local lists of purchases. See Apple's Receipt Validation Programming Guide: https://developer.apple.com/library/ios/releasenotes/General/ValidateAppStoreReceipt/Introduction.html#//apple_ref/doc/uid/TP40010573-CH105-SW1
Restoring purchases should be a user-initiated operation, with dedicated UI (a restore button in the store somewhere) separate from checking if a purchase has been made.

Answer 2

Should I be utilizing NSUserDefaults to avoid restoring purchases in the future?
You need to avoid NSUserDefaults for IAP. NSUserDefaults are stored in plist in binary format, with no encryption. If you need security you should use KeyChain. It encodes values and is best way to save some security information.