QR Code with Shopping Cart App for iPhone

My client is interested in building a simple app that allows users to use their iPhones to purchase products in a department stall, through QR codes. When a QR code is taken, it will access a database to retrieve Product Name and Cost unique to the QR code. Users are able to capture more than 1 item, and add it into their shopping cart. Once the purchase is done, the data will be sent to a database online. The project will also need to a simple registration page to capture the user's information, such as User Name, Address, Contact Number, on the iPhone. Lastly, there will be a need to have a simple web interface for the administrator to add new QR codes ID, Product Name and Cost into the database. In addition, the administrator will be able to log into the system to check the orders that has been made. This project is a proof-of-concept for the client. Once the proof of concept has been approved, the client will proceed on to the full development of the system, which includes the development on other mobile device platform as well. The next phase of the project shall be given to the winner and eventual developer of this bid.