What could the population of Wikipedia users using the mobile app and looking at articles that have map info be on a given day? 12?
Check out the Millennium Series by Stieg Larsson (Girl with the Dragon Tattoo, et.all) and some Heinlein - Stranger in a Strang Land, The Moon is a Harsh Mistress, Starship Troopers.
Okay. You go do something else then. I'll be a financially-secure multimillionaire. It's going to suck so bad...
This site lets you create QR codes with various info in them: http://www.qrstuff.com/