Steam's Android app has thrown up a selection of new categories that point to the possibility of productivity apps and other types of non-gaming software being sold in the near-future. Ranging from photo editing to accounting, there's ten categories that aren't available on the desktop version. It would open up yet another branch for Valve, which already offers books and movies through its online store, but until these categories get fleshed-out -- they're currently empty -- we're left guessing as to what it's