Booking.com's mobile bookings tripled last year, reflecting how quickly Europeans are adopting smartphones to make their hotel and airline reservations.
Booking.com, a division of Priceline, processed about $3 billion in mobile travel reservations in 2012, up from about $1 billion in 2011, Priceline said.
Priceline said Booking.com’s mobile apps have been downloaded more than 20 million times during the past three years.
Priceline in January launched its first U.S. ad campaign for Booking.com.
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