Write iPhone requirements specification?

What do you use to draw iPhone ui and 开发者_StackOverflow中文版write iPhone requirements specification?

I use balsamiq mockups to draw up the screens, then I write a up a page for each screen explaining behaviors

There are a number of stencils available out there for OmniGraffle and for Photoshop. I've used Omnigraffle before to create images and drop them into a Word or Pages document.

Interface Builder generally to mock up a UI, and I typically write out spec informally in notes. However, if I were submitting these to other people (i.e., a contractor or subcontractor) I'd probably be using Pages or something similar to take my informal notes, and present something formal.