These founders literally walked the streets of New York in their quest to map the city. Now they're offering their interface to developers.
In 2010, Citymaps was a fledgling idea scribbled on a cocktail napkin at a Manhattan bar. Cofounders Elliot Cohen and Aaron Rudenstine had no experience with maps, but knew they wanted to build a map app people could use on their smartphones. "Why reinvent the wheel?" most people told them. Wasn't Google Maps good enough?