A good start – Apartments & Rentals by Walk Score - Find Your Apartment for Rent, Condo, House or Home Review

This app is great for when you're looking to move. Helps evaluate different locations. But I wish the app also helped people who aren't moving and just want to explore their area, see what's walkable.
Review by CalifDude on Apartments & Rentals by Walk Score - Find Your Apartment for Rent, Condo, House or Home.