Kayak for the iPhone and iPod touch, connects to the best travel search engine in the world. This app lets you quickly find the best prices on airfares and hotels with your mobile device. You have the option of booking online or, using the iPhone, calling the airline or hotel directly if you need to reach a representative directly.
As you would find with the Kayak website, you can search many airline's websites at once, then choose the once that fits your price and time choice. Then it's a matter of easily booking the hotel.
Unlike some other travel applications available at the iTunes store, this iphone app is free! In a world of doing things on the fly, great apps like this make our busy and complicated lives a little easier.