proximity iphone app that references local businesses

An iPhone proximity app that tells you about certain businesses that are near you. The businesses will be of a certain type that you will learn about after you sign non-disclosure agreement. The app will be simple in that it'll have a single page with several pulldown options which are all optional. If you want you can just click "Find". The app will show you either a list of the closest businesses or map view. Clicking on the listing or the map marker will show you more info so you can contact the business. So, I need an app builder that has experience with the following: 1) building an IOS5 app 2) building proximity app 3) referencing a yellow pages (or local business) database so we can check locations against user location I might port it later to more phones.