One of the coolest things about traveling is the chance to try new restaurants. You can't really rely on airline magazines or those in-room hotel "city guides" for the skinny on where to go, but you can rely on other munchers. The iPhone app connected to Yelp's social-review platform lets you access the wisdom of the highly opinionated Internet masses for dining tips. From there, the Yelp app's "Nearby" feature shows you in both list and map format which recommended restaurants are close by. Or you can bookmark the best spots to check out at a later time.
Yelp App: free