Cost: Free
Track your routes and miles with Map My Walk by Under Armour. The app gives you feedback after every mile; as you walk, the app uses GPS, so you can see your distance, pace, speed, and calories burn over the elapsed time. You can save your routes to keep a log for reference (or social media bragging rights!). Plus, you can choose another route that a nearby Map My Walk user uploaded. You can even connect with friends to motivate one another.