You want to go on a trip and your loyalty to any one carrier is only superceded by your desire to save money. That's where KAYAK Flights App for iPad comes in. This free App allows you to put in your destination and the dates you want to travel and then it goes out and searches for the flights headed there and then sorts the results by the lowest fares. If you decide to go with one of the fares you found you can tap to book it, but you'll be taken out of the App to book the flight on Orbitz or whichever site had the lowest fares. It would be nice to be able to do it all in the one App, but it's not the end of the world that you leave the App once it finds your fare. KAYAK flights can also search for Hotel and Car Rental discounts, but again it does so outside of the App. The App is free and really only geared towards Flight searches. 

You can download it here for your iPad or here for your iPhone/iPod touch.