Here's another interesting, fun app for historical types: Streetmuseum Londinium. It directs users to locations around Roman London. As you stand in modern day London, the app gives details about your location as it would have been in ancient Londinium. Key locations include the amphitheater and the Temple Mithras, as well as a map of ancient Londinium superimposed on a map of modern London.

Right now probably wouldn't be the best time to be wandering around London, with an iPhone in one hand and a soft drink in the other, searching for ancient locations. But just browsing through this app really makes me want to visit London some day.

These kinds of apps should be great for history buffs and school kids.