IPhone with the .Net Application

Hai Friends,
Is anyone working on the IPhone application development?I need some sugestions regarding that.
Actually I have an application which is developed in the .Net technologies. The Application need to be working in the IPhone. Also its like taking the order using the IPhone. The database will be centralized in the Shop.
So the requests will be taking in form of order in the IPhone and this IPhone request should go and intimate or update the DataBase which is located t the centralized location.
How we can connect and make this scenarios as working. Do anyone is having the idea about that? Can we make the request from IPhone to the Database using some sort of WiFi or Bluetooth connection?
If anyone is working with IPhone application or Mobile devices or touch screen devices, please contact me..as its very urgent.
Thanks in advance.