Yapta is a free Firefox addon that lets you plan and travels your money by tracking airfare for the flights you want to take and notifies you when prices drop. Moreover, it will let you know the lowest price available even after buying the ticket and makes you eligible for vouchers or refunds from the airline.
At the same time, using this addon, you can easily compare the best fares on airline websites. When you use Yapta to search flights, a sidebar notepad will intelligently open to display the My Trips list. Each of the times, the flight you tag will be added on the sidebar notepad and the addon will begin tracking prices.

With Yapta’s add-on for Firefox, you can:

•Instantly confirm that Yapta has begun tracking prices on the flights you’ve tagged

•Quickly compare flights you’ve tagged while shopping multiple airline sites

•Get email alerts when prices drop. Get credits or refunds from the airlines.

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