Produced by ITA Software, OnTheFly showcases their experience with reservation and inventory management software. The interface is easy to use, the results are speedy, and it's easy to tweak search parameters like dates, pricing, number of passengers and more. OnTheFly is location aware and will automatically search for the best airfare from the nearest airport.
One thing that is absent from OnTheFly is a built-in method for booking your flight. OnTheFly has no built-in booking mechanism for ordering tickets directly from your phone, but once you've found a flight or set of flights you're looking for it does provide easy information for you to call and book a flight. Every listing has a "How to Book" button which gives you the customer service number of the relevant airline and all the information you need to give the ticket agent in order to book that specific flight.
OnTheFly is a free app and available for both Android and iOS phones. Visit the link below to download a copy for yoru respective smart phone OS.
OnTheFly [ITA Software]