KAYAK is a travel app that searches hundreds of travel sites to find the best deals for flights, hotels, vacation rentals, and car rentals. The app allows users to easily search, filter, and sort their options to find the right travel offers for them. Users can book flexibly with flights they can change with no fees, hotels, vacation rentals, and car rentals with free cancellation, and the cheapest deals. The app also offers mobile-only rates and Private Deals, as well as Price Alerts to notify users when prices drop.

KAYAK's Trips tool keeps users' plans in order by providing alerts for flight and gate changes, access to boarding passes on and offline, and the ability to plan and share itineraries all from one place. Guides allow users to create, collect, and share daily itineraries, tips, and impressions along the way. The app also offers an AR measuring tool to ensure users' carry-on bags comply with airline policies.

With KAYAK, users can compare flight deals from over 900 sites, filter options based on stops, airlines, departure times, cancellation policies, amenities, and more. The app also offers Hacker Fares, which pair together two one-way tickets for a round-trip flight and save users money. Users can find a rental car that fits their trip by searching from over 70,000 locations and filtering their search by vehicle type, offers with unlimited mileage, enhanced cleaning, and more.

KAYAK also allows users to compare all sorts of accommodation, from five-star resorts to holiday homes and boutique hotels. Users can stay flexible by easily filtering for hotel deals and vacation rentals with free cancellation. The app also offers Private Deals and exclusive mobile-only rates for even more savings. Explore lets users discover new destinations on their budget by setting a budget and showing them where in the world they can go.