Write an iPhone application - trade services directory similar to hipages.com.au app

similar to "hipages" app. we are looking to have someone build an app where customers can search for a tradesman (for example, plumber or electrician). we will be listing one business for each trade category in each postcode. they need to be able to do this by touching the category on front screen, then the next page needs to allow them to enter a postcode/suburb name for their area. this should then direct them to a page with some basic info about the listed business, with 2 options: a one-touch button to call the business phone number, & a one-touch button to "send an enquiry". the enquiry page needs to have the following fields: Name, Phone Number, Email, Message/Job Details. Also 2 drop-down fields: "Your Budget" (which will have about 10 pricing options), & "When?" (which will have clickable options such as "like yesterday", "within 24-48 hours", "next week", 'next month", "pretty flexible". Also need a "log in" option on front screen for customers so that they can have most of their information pre-filled. Also a "list your business" button on front page so that trade businesses can send through an enquiry about listing on the app. On the back end, we will need to be able to control our own database of listings on the app, so that we can update the links for phone and emails for the trades listed etc.