This comprehensive search engine mines mountains of datafor the best prices on airlines, hotels, and car rental sites. Flights can be sorted by price, duration, number of stops,airports, and layover time; we love the “buzz” feature, which shares the best fares foundby other users. (Fare history is envy-inspiring, but ultimately useful.) You can reschedule missed or canceled flightsdirectly through your phone, too. With hotels, you can search for deals for tonight or by rating, price, brand, or distance from wherever you want to be.
Free for Android, BlackBerry, iPhone, iPad, Windows Phone; www.kayak.com/mobile.