There seems to be an issue with the download. After purchasing it redirects to a download page but when clicking on download nothing happens. Other users on Reddit are reporting this too. Hope it gets fixed or refunded.
Same issue here on an iPhone SE. Also tried on an iPad, where I got a pop up “you can only install this marketplace on an iPhone”, which is disappointing.
Apple claim that the iOS App Store is a separate entity to the iPadOS App Store, and thus, doesn’t qualify as a gatekeeper under the EU DMA. Apple have made alternative app stores only available to iPhones running iOS 17.4+.
Apple may benefit from you registering your disappointment with them directly, so that they can stop bragging about their immense customer satisfaction percentages in future product launches.