Online travel sites mediate between you and airlines, hotels or rental car dealerships to get the best price. Kayak's website is simple and minimalistic, with only the search bar and booking tabs at the top of the page and rates for popular destinations below.

Kayak lets you search for the same booking on other discount travel sites as well. Comparative prices are a great way to cover more virtual ground by searching multiple sites at once. When you search for fares, the comparative pricing appears as new windows, even if you're using a small mobile device. This can be a great tool when you intend to use it, but an annoying surprise if you don't want to compare prices. If you don't want to see other prices, you can toggle the price comparison on or off.

After your initial search, there are basic filters to sort your results. If you're new to using the site, it may appear that you can't refine a search for a hotel other than by location and date. However, you can expand the sidebar menu for more options, like star rating, amenities or flexible dates.

While you can catch a flight or reserve a hotel room almost anywhere, you can't book any cruises on Kayak. It also misses the mark on multireservation packages. You can only book flights and hotels together. Most other discount travel sites offer multiple combinations for vacation packages, typically letting you book flights, a hotel and rental car together or in some other combination.

Kayak's most outstanding feature is the mobile app available for Android and Apple devices, Windows phones and Kindle Fire. You can book flights, hotels and rental cars, compare prices, set alerts for the right prices, and check your flight status through the app. The booking features on this app are easy to use and work quickly. It includes extra features like a customized packing list, currency converter and the airline directory. Outside the app, you can find similar helpful tools on Kayak's website. The Explore tool shows you rate averages for popular destinations around the world at any time of the year. You can also set up email alerts to notify you when the best prices for your trips are available.

You can contact the company using its telephone or email support. Kayak also has a FAQs section on its website.

Kayak is missing some common features, such as the ability to book a cruise. However, you can still catch low rates for flights, hotels and rental cars around the world. The site design is simple and streamlined, with options to expand search options. While Kayak's website is aesthetically pleasing, the mobile app has some extra features and is the best way to use this discount travel site.