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I was going through the Apple Pay documentations and found the following guidelines from here - https://developer.apple.com/design/human-interface-guidelines/apple-pay/overview/checkout-and-payment/ Accelerate single-item purchases with Apple Pay buttons on product detail pages.  In addition to offering a shopping cart, consider putting Apple Pay buttons on product detail pages so people can quickly purchase an individual item. Purchases initiated in this way should be for an individual item only, and should exclude any items that already reside in the shopping cart. If the shopping cart contains an item purchased directly from a product detail page, remove the item from the cart after the purchase is complete. Accelerate multi-item purchases with express checkout.  Consider providing an express checkout feature that immediately displays the payment sheet, allowing people to quickly purchase multiple items using a single shipping method and destination. My current implementation is like from Cart I will go to the delivery address page. Then I will show a summary of order. In that page I have added a button which lists payment options available. First one is "Apple Pay" then other options. So my questions, Is it mandatory to add the Apple Pay button to the product details page? Is express checkout is Mandatory? Is there a chance of rejection if I did not follow the above options? Is my current flow, against Apple Pay guidelines? Can anyone help me to get an answer for the above? Any help will be appreciated.