Tried it on the iPad. It is bad. Same lacking formatting mentioned earlier of course, plus I forgot to mention there is no two-page landscape view. Another thing, I got an error on a Topaz book purchased through Amazon. That makes sense but it does present a shortcoming for this new reader. The Topaz did display, but it was messed up a bit.

@jocampo, my Moto Atrix has a 4" screen but a resolution on par with the iPhone retina display, which means no fuzzy letters like the iPad. I get extremely sharp text that is much easier to read than the iPad and equal to the iPhone. But on my phone I use FBReader because I can use side loaded fonts. Unfortunately that means converting the mobi to ePub, but that takes very little time or effort. Btw, The Atrix screen has nearly as many pixels in 4" as does the iPad in 9.7", and that makes for a stunning display. I find that I can comfortably read the same amount of text displayed on my K3 on the smaller phone screen, which means using a smaller font size on the phone. But since the dpi rating of the phone is almost twice that of the K3 the smaller font size is just as readable on the phone as the larger font size is on the K3. The same can be said for the iPhone retina display though you get a little less text on it because it is only 3.5". The K3 is still my preferred reader though.