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Dear Apple team,I am developing an application offering online video courses which user has to purchase. I know I need to use In-app purchase for digital content in app. But my question is:For static products like $5,$10 etc, I can easily add product IDs in iTunes connect and later I can display on application using store kit(I have worked on consumable and auto renewable IAPs with fixed price). But In our current application, price will be dynamic.Example: $15 or $45 or $345 etc based on user selected content on their cart. Price will be multiplied by the items quantity like any E-commerce application.Suppose I have added a video course of price $10 and quantity 5 in my cart. Later I have added one more course in my cart which is a cost of $20 and quantity 1.So total amount I have to pay is when I click Buy Now: $10*5 + $20*1 = $70.On the other hand, android people are using credit card payment. But in iOS you are not allowing to use other third party libraries other than In-app purchase. So please help me with this thing, which way I need to follow?If I am using In-app purchase how to achieve this? Or If I use credit card payment or PayPal will you reject my application?