public virtual void ProductsRequestDidReceiveResponse(SKProductsRequest request, SKProductsResponse response)
        {
            NSArray products = response.Products;
            NSArray invalidProducts = response.InvalidProductIdentifiers;

            foreach(SKProduct product in products.GetEnumerator<SKProduct>()) {
                Console.WriteLine(product.ProductIdentifier);
                Console.WriteLine(product.LocalizedTitle);
                Console.WriteLine(product.LocalizedDescription);
                Console.WriteLine(product.Price);
            }

            request.Autorelease();
        }