you need some way to decrypt the app store app so you know what you are modifying and so you can resign which usually involves a jailbreak. maybe there are thes

you need some way to decrypt the app store app so you know what you are modifying and so you can resign which usually involves a jailbreak. maybe there are these apps that only have the first page encrypted so potentially you don't need to decrypt these apps because you can guess what the first page is.