RoadNinja - Always know what is coming up at the next exit and compare gas prices at upcoming exits.
Tipulator - Makes tipping easy even with split bills.
PhotoSynth - Enables users to take awe inspiring panoramic pictures in an instant and is fully integrated with Facebook.
AlpineQuest GPS Hiking - Comprehensive orienteering maps come complete with contour lines.
ExpertFlyer - Get notified when seats become available.
Groupon - Find 50% to 70% off restaurant offers.
Schemer - Users leave recommendations for things to do in their city and visitors can add to a to do list and check off as they go.
myLanguage Translator Pro - Translate text into spoken voice.
Air Sharing - Turns your iPhone into a wireless hard drive, allowing the user to quickly load documents at the airport that can be viewed in flight.
Ski & Snow Report - Get the latest ski reports with detailed trail maps.
World Clock - Time Zones - provides easy access to the time in hundreds of cities and adding several clock as home screen widgets.
Zagat - A guide to discovering the best restaurants, bars, cafes and clubs.  Started with nine cities (Austin, Boston, Chicago, London, Los Angeles, New York, Philadelphia, San Francisco, Washington DC) with more on the way.
HopStop - Offers public transport information on 68 of the world’s biggest, busiest metropolitan hubs.
Instagram - Coverts photos into works of art. Instagram gives photos professional, antiquated, or artistic looks. It makes sharing pictures across social media networks easy.
Hailo - Uses cell phone’s GPS to make cabs come to the user.   Available in six US cities/15 worldwide.