Be aware that you must first apply to become an Apple Developer (enroll in the paid Apple Developer program) and that is a complicated task if at all possible and you must pay $99 a year (renewable every year) to Apple in order to become an Apple Developer (even if you are not a developer at all) so that Apple allows you to begin to apply for an Apple Merchant ID and other things required to set up Apple Pay. Even Apple support had problems handling this and will send you around. And Apple forums will delete your post if you ask the question about the $99 yearly fee to enroll in the Apple Developer program. Apple Inc. describes the Apple Pay handling as done in a couple very easy steps, which is a big lie. Be aware of this when ordering this software. This sales page does not disclose the fact that you must first become a paid Apple Developer at a cost of $99 per year. Also, you must own an Apple iPhone or similar Apple device in order to go through the process. And even that does not guarantee that you will be able to accept Apple Pay. It's a very complicated matter that I have gone through and failed to want to purchase Apple device and pay $99 yearly just to accept Apple Pay occasionally and pay Apple even more in credit card processing fees. So no wonder there is no information on X-cart forums and other online sources on Apple Pay, because so few people were probably able or unable to master it and to make it work and very few want to pay Apple money in order to pay them even more in fees and charges. And no wonder so few merchants accept Apple Pay or uses it to pay.
I also must add that there are no user instructions for this software neither knowledge base on using Apple Pay for v4. If I am proven wrong I will update this review.