If you have an application (mobile, web, or even a basic interface) make sure that you check out JQuery Mobile for prototyping.
Why? The IPhone style interface provides a very tactile interface where users can input information. The user experience is also simplified because many users are already accustomed / memory mapped to the controls.
There is also a new feature to the JQuery Mobile web site which will help your implementation and use through a Codiqa drag and drop interface builder (making it slightly simpler (and a lot easier for web devs to add logic) than the XCode interface builder.
The attached image is a quick project that a friend asked me to look into that now just needs a quick scaffold for database interaction.