The Field Trip app, optimized for iPhone (not iPad), is a guide to "the cool, hidden and unique things in the world around you." Once the app is fired up, it will run in the background. Relying on your cellphone's signal with surrounding cell phone towers, the app will know exactly where you are and when you're approaching something noteworthy.
The app will surface little tidbits about architecture, historic places, events, offers, deals and cool facts about heat you're seeing automatically. You'll know the exact locations of trendy places to eat and drink -- including the hidden gems only locals know about. It's like having the world's best travel guide in your pocket.