iPhone App, needs to use API to link to WHMCS system

Looking for a very experienced App builder, also must have experience with API, as the app will be fully integrated into our WHMCS system which will link in using API's. Design is a huge part of this project, I have images of screenshots of what I want the app to look like. When the app is launched, it will show a splash screen for 2-3 seconds which shows company logo. Then it will have a screen with has the company logo, below this it will have a box for email address and a box for password and a Sign In button. at the bottom of the screen it will say New User? Register Now. Clicking register will make a new screen slide down, at the top a drop down with Countries, below this fields to enter Email Address, Password and Confirm Password. Then have a next Button Next Page asks for First Name, Last Name, Company, Mobile Number. Then have a button at the top for Next, next screen will ask for Address Line 1, Address Line 2, Suburb or City, State (will only show available options based on the country they selected on first screen) and Postcode. Then press Next at the top. The next screen will show an option to view Terms of Service, Privacy Policy and a few other documents, below this it will just have a few dot points they read, and down the bottom a button that says Agree and Create Account. The app will then compile all the inputed info and use API's to register the account on our system (WHMCS) Once registered and logged in clients will be able to see their account, from the main screen, where they can update their details, tabs down the bottom, with options to register domain, transfer domain and renew domain. It will use API's all through the app to interface into our system, for things like registering domains, customers will be able to enter their credit card via the app, which is stored in our system or pay using the card that is already stored in their account. It will also allow them to view the balance on their account, past invoices. There will also be an option for sales, clicking that will allow the client to write a message/support ticket, which will be sent through API to our system. There will also be a support tab so clients can raise a support ticket from the app. So That's a detailed rundown of what I'm after. I have images of what I want the app to look like, know how I want it to work, Have the API documentation and keys to integrate the app into our current client management and billing system, and have images for logos, buttons, backgrounds and more. No deadline on this, just looking to find a developer who will be able to design a beautiful app and is fully functional with our system. If you cannot deliver on the above do not respond to this as it will just be a waste of both our time. Like I said experienced developer who is up to the task would be good to hear from. As a guide, the following apps are what type of designs we are looking for... The PayPal app (how it looks and works such as Login screens and register screens) Apple Find My Friends (login screen and register screens) If you are interested be good for you to download these apps, and take a look at them, as those are the kind of designs I'm looking at