Detour - Immersive audio walks, now in 17 cities
Simmer (formerly Foodie) - Yelp, but for every dish on the menu
Sygic Travel Maps - Itinerary planner for independent travelers
Spoon University - Food network for next generation.
Flamyngo - Create a city guide with help of your friends.
NYT Cooking - iPhone app with 17,000 free recipes from The New York Times