Write an iPhone application

I need an Iphone application built. The application would be like a platform where sellers will be able to list items, and after they list it the item will be accessible through QR code only. Direct link access should redirect to homepage of the website. The website will serve as a platform where the seller can Add products to some sort of catalog but this catalogue is not public, its accessible only via QR code and the buyer makes an account through our app where he has his information such as CC address email etc