One of Hipmunk's newer features--and one that vaults it to the head of the class for iOS travel search tools, in my estimation--is its ability to integrate calendars into search results. All you have to do is flip a switch, and Hipmunk taps into the calendar data stored on your iOS device. Search for a flight, and Hipmunk will display appointments you have on its Gantt chart of flight times, so that you can see if your flight conflicts with a can't-miss meeting. For hotel results, Hipmunk displays where appointments you've scheduled are located in relation to your hotel--a really important piece of information that's helped me plan business travel recently.
You could try any one of a number of free search tools from the likes of Kayak, Expedia, and whatever travel site you care to name. But save yourself the time and jump directly to Hipmunk's offering for a clean app that really takes advantage of Apple's mobile operating system.
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