When you're traveling, your smartphone's more than just a way to while away time in the airport. Your phone can also become your travel agent, personal assistant, interpreter and guide. See how much easier your next trip becomes once you download these popular iPhone and Android travel apps.

Top travel apps for booking travel

Many travelers use Kayak as their go-to travel app. A clean interface makes it easy to search for hotels, flights and car rentals, showing the lowest price available through other travel sites. Kayak also throws in a few bonuses, such as real-time flight tracking and more than 100 airport terminal maps. Orbitz is another popular travel app that's highly rated for its simplicity and speed. Users say they can book a flight in three minutes and find deals on hotels and cars to boot. TripAdvisor's app offers the same services, plus millions of travelers' reviews.

Top travel apps for your journey

You blinked and missed the highway sign telling you what's at the next exit. Is it the gas station you desperately need? Or a rural crossroads with nothing but cow pastures? With the iExit Interstate Exit Guide travel app, you'll never have to wonder. If you're traveling by plane or train, try TripIt. This award-winning travel app takes all the confirmation emails tucked away in your inbox and automatically organizes them into one easy-to-read itinerary.

Top travel apps for finding a place to stay

Airbnb is a mobile matchmaking app that helps travelers rent rooms and apartments from people in more than 190 countries. Search by destination and date and browse accommodations, from guesthouses in Kathmandu to luxury flats in London. If you like to fly by the seat of your pants, try HotelTonight, a travel app that helps you book same-day hotel stays for up to 70 percent off. JetSetter (iPhone only) offers similar discounts on hotels and vacations, with the bonus of being so beautifully designed that many users just enjoy browsing the possibilities.

Top travel apps for your destination

Yelp is a favorite travel app. The mobile version of the popular restaurant-review site makes it easy to search for highly rated eateries and other businesses nearby. Going somewhere new and you don't have any idea what to do? Tripomatic is the answer. This fun travel app for iPhone suggests activities and attractions to visit and maps them out for you.