Nice, but ultimately useless as it does not reproduce iSafari selective font resizing (for h1/h2/h3) that tends to screw up a lot of websites.<p>(edit) On a more general note, <i>emulating</i> behavior of a browser/OS combo is not a very good idea as it is trivial to miss quirks that need emulating. It should really be taking an actual browser screenshot on selected device, but then it would've not been different from a ton of similar services... which arguably sprung up because they <i>are</i> doing things rifht and therefore <i>are</i> useful.