- Love that I can set my location and it suggests me dates with the cheapest airfares.I'd also highly recommend Skyscanner! You can filter the results with different criteria, so if you only want direct flights, you can get rid of any that involve transfers. It also lets you search for nearby airports to find the cheapest deal. My only criticism is that Skyscanner doesn't take into account certain fares - for example, SAS does 30% discount for under 26s, but Skyscanner doesn't show this.
- Crazy amount of control with search queries that enables flexible travelers to get the best rate.Yeah, Google Flights is my go-to. It's got loads of flexibility, and it's really clean. No pop-ups, no attempts to sell you other stuff. The rates tracker is incredibly useful, too.
- I use Momondo - only their hotel search product is listed here, but I've found amazing deals through their flight search engine. They have a "flexible" option so you can get the cheapest date to go to your destination.
- the only one service which shows you flights with hidden-city optionDefinitely Skiplagged. I've saved hundreds of dollars on flights with it... for example, turns out a flight from Cleveland --> Houston --> Cancun is $300 cheaper than a flight from Cleveland --> Houston. That's what Skiplagged can show you. It's wonderful.