Knapsack - Plan your trip and later share memories.
Seatguru - Shows the best seats on every plane and where power ports are located.
FourSquare - Turn on this app upon arrival and see a list of tips from those who have been there before you.
iMuseum - A web tracker that searches via GPS the closest museums in your immediate area. Updates museum news and exhibition info regularly.
Instagram - Coverts photos into works of art. Instagram gives photos professional, antiquated, or artistic looks. It makes sharing pictures across social media networks easy.
Tipulator - Makes tipping easy even with split bills.
Google Goggles - Search by taking a picture. Users can point their cell phone cameras at paintings, famous landmarks, barcodes or QR products, or popular images. If Goggle finds it in its database, useful information will be returned.
Foodspotting - Focuses on specific dishes with user generated recommendations.
EveryTrail - Track, share and explore.  Plot your trip, photos, and video right on the map and upload it to EveryTrail, Facebook, and Twitter.
Perfect World Clock - Provides easy access to the time in hundreds of cities adding several clocks as home screen widgets.
Lemon Wallet - Allows user to store a digital copy of all cards – ID, insurance, loyalty, and payment card, so that they can be accessed whenever needed.
Urbanspoon - Shake your phone and the Urbanspoon slot machine will suggest local popular east via the GPS in your phone throughout the US, Canada, UK, and Australia.
Where To? - Enables user to locate almost anything nearby, including the nearest ATM, burger joint, and medical provider. 
Waze - Provides user submitted traffic report to offer the fastest route for current road conditions.
Tripit - Combine all your travel reservations in a single locations.