2. Hopper
Hopper is a very cute looking app which is a fare hunting powerhouse. It not only finds the lowest flight fares based on your travel days, but also provides proper advice whether you should book the flight now or not. It can further predict whether the prices of such flights would go up or down in the future from where you can use this fact to make your purchasing decisions wisely. In addition, it keeps you sending notifications of all the changes that are going on in the airline industry and the changes in the dollar rates so that you can make proper decision. Sadly again, this app is only available for iPhone users.