Walkability: it's an elusive measurement of a given area's walkable quotient, or how easy it is to get around by foot. Residents are generally happy to be able to walk more, Millenials are flocking to walkable urban areas more than ever, and organizations are popping up supporting Smart Growth in urban areas.
And it's also good business: recent research suggests that walkable streets can increase property values by up to £30,000, in addition to increasing shop foot traffic by 20-40%. In the US, walkability has also (surprisingly and thankfully) become a very visible component of home selection and lifestyle consideration.
A new app called Walkonomics aims to bring this information to those afoot in San Francisco, London, and England. The app aggregates information from the primary Walkonomics.com site, in addition to several other publicly available data points.
The app aggregates the following:

The Walkonomics app uses over 600,000 street ratings from Walkonomics.com, covering every street in San Francisco, New York and England. But unlike other walkability apps, which only measure how many destinations are within walking distance, Walkonomics provides 5-star ratings for 8 different categories of pedestrian-friendliness:
Road safetyEasy to crossPavement/SidewalkHillinessNavigationFear of crimeSmart & beautifulFun & relaxing.
These ratings are generated from Open Data including street widths, traffic levels, 311 cleanliness reports, gradients, crime statistics, pedestrian accidents and even how many trees are on each street. This automatically generated data is complimented by crowdsourced reviews from local residents and visitors. Each street rating is mapped using colour-coded markers to show the overall walkability rating for every street.
While currently limited in location scope, the app does a good job at leveraging Open Data to provide information that might not have been easily accessible in other venues. These are the sorts of use cases for Big Data and Government 3.0 that provide very real value for both citizens and businesses looking to make informed decisions from a robust data set.
For travel business, hoteliers and restauranteurs considering site selection in these cities, this app is a useful tool to see just how walkable an area is - and how it might affect profitability.