App for iPhone/iPad. Scanner for retail store.

I need someone to write an app for independent Retailers. The app needs to work for iPhone and iPad. The app will need to be able to scan a barcode from a product and add this to an order. Retailer must be able to order multiples of the required product if needed. The app must be able to link with an outside website accessed via a login and password. The retailer will need to have live price information and have the ability to create 2 orders at the same time, possibly for different types of products. The app must also be able to link directly to the website to access order history.