We’re working on an iPhone-optimized version of Ta-da List.

As I was working on some UI ideas, Ryan and I were talking about some of really cool things about designing for the iPhone.

I remarked that I loved the constraints. For example, we know the exact screen size/resolution, we know the exact typeface, we know how the face renders on the screen, we know the colors, we know the browser, etc.

Then Ryan nailed it: Designing for the iPhone is like a hybrid of print and web design.

The web we all know is rife with uncertainty. We don’t know the viewer’s screen size or resolution, we don’t know the gamma of someone’s screen, we don’t know if they’ve got a certain typeface and/or exactly how that face renders on in their browser, we don’t know the browser they’re going to use, etc.

But paper, on the other hand, is full of controls. Fixed size, fixed faces, fixed colors. What you print is exactly what someone sees (assuming you’ve done your homework on color and paper, etc).

So the iPhone is a weird mix. It’s the web, and things can scroll, and the data is pulled from remote servers, but it’s also a fixed width, a fixed browser, fixed typefaces, etc. It’s pretty cool and a really refreshing design exercise.

In other ways it’s also like going back to the early days of the web when people’s connections were a lot slower. The EDGE network and mobile phone latency emphasizes the need to keep page size down, images sparse, etc. It’s a return to the power of text, shape, color, and basic HTML.

I love it.