Smartphones and tablets together account for 21 per cent of hotel bookings globally, according to a report from ad tech firm Criteo, a figure which rises to 34 per cent specifically for peer-to-peer apartment rental services like Airbnb.

Mobile bookings are growing 10 times faster than desktop (20 per cent and two per cent respectively over the first six months of 2014) and in most cases also seem to be more valuable. The average booking value for air travel was 21 per cent higher on mobile than desktop, and 13 per cent for car rentals – though hotel booking values were actually 30 per cent lower.

There’s a particularly sharp boost in value on iPad, which sees an average extra $600 (£368) spent on packages compared to all Android devices.

“Mobile is the driving force behind the exponential growth in online travel booking and sales, and that’s only set to continue in the second half of this year and beyond,” said Jason Morse, vice president, mobile product at Criteo. “Determining budget across desktop and mobile must be completely fluid because consumers are making decisions in real-time, requiring that the booking experience be streamlined and integrated with mobile-friendly payment systems to ease the all-important path to purchase.”