Check out crime faces of Arrested! Mobile Mugshots
It could be you

Depending on your point of view, Arrested! Mobile Mugshots is either a hilarious app highlighting the grim-faced American underclass or an interesting psychological window into the human condition.
Personally I just like looking at the quality of the photographic set ups of the various US gaols, not to mention the Hogarthian quality of the faces themselves.
It's like a street version of Hot or Not!
More prosaically however Arrested! streams the mugshots of people who have been arrested on various charges. Presumably the US has different privacy laws to Europeans as you can also view the names, date of birth and charge sheets of the individuals concerned.
Of course, this means you'll need either a wi-fi or 3G connection to view the faces and app's performance isn't the best: just launched presumably it's quite popular. Still it's free - ad supported using the GreyStripe system.
Arrested! Mobile Mugshots is available now. Hit the App Store button to get it.