I'm not sure about the usefulness of coding UI prototypes. When I owned a web design firm, if the UI wasn't polished, clients had a hard time wrapping their he

I'm not sure about the usefulness of coding UI prototypes. When I owned a web design firm, if the UI wasn't polished, clients had a hard time wrapping their head around the design or what the final product might look like. In every case I remember we had to make it pixel perfect in the design phase and then again in the development phase. It was a huge pain and an area ripe for innovation but I think the problem like other posters have mentioned is a lack of quality responsive design tools that are better than simple HTML/CSS design in the browser.