In fact, Hitler doesn't appear at all. Instead, MAUS is at once a novel, a documentary, a memoir, an intimate retelling of the Holocaust story as it was experienced by a single family - Speigalman's own. Or rather, by Spiegelman's father, Vladek, who recounts the story to his son, Art, who was born in 1948, after the war was over. The story deals as much with his father's reminiscence as Art's tortured relationship with his father. I missed the visceral thrill of turning actual pages, and as a long time fan of comic books, I couldn't help feeling that certain stylistic aspects of the individual pages were lost in it's translation to electronic form.
Comics are a visual medium, and many stylistic aspects are dictated by the size of the page.
While the story may flow from one panel to another, the way each page is set up is often important, either symbolically or aesthetically. For example, panels and images arranged in a certain way can evoke memories of previous pages with a similar format or image. Alternately, some graphical element may take up the entire page, and the fact that you can only view half the page hinders the reader from appreciating the full beauty or complexity of the page. You can still zoom out to view the page in its entirety, but it's still not quite the same. In addition, I found the interface inconsistent and unintuitive.