Classy: Expressive, flexible, and powerful stylesheets for native iOS apps

This seems like one of those things that should've existed from the very start.

It's certainly cool, but it is kind of opposite to the whole idea of having Interface Builder in the first place.

Not really. It would be awesome if iOS had a system like this (or similar to Android's style engine) and it were reflected within IB.

As it is I setup all my UIAppearance proxies in code and things look weird in IB (which confuses my designers until I actually show them the running application).

It would be great to have a comparison with Pixate.

It would be nice to have a demo or screenshots.