Credit Card Processing App for iPhone

Interested in creating an Application for the Apple iPhone that allows users to accept credit card payments using their iPhone. There are already several Apps on iTUnes that do this. You can look at Inner Fence Credit Card Terminal, AppNinjas iSwipe Pro Credit Card Terminal, Spartadata Billing: Credit Card Terminal, and MerchantWarehouse Accept Credit Cards. There would be two components to this project. 1. Replicating the front-end / user interface of one of these products. 2. Enabling communicatino between the user's iPhone and the credit card? payment gateway, which could likely be Authorize.net. Ideally, we are looking for an organization with iPhone development experience and experience with credit card processing or at least payment processing applications. Thanks!