NEW YORK: Mobile apps generate almost half of all mobile transactions for some of the largest ecommerce players who have made their app experience a priority, due to much higher conversion rates than mobile browser or desktop.

That is one of the findings of the Q2 2015 State of Mobile Commerce Report from Criteo, a performance marketing technology company which analysed 1.4bn ecommerce transactions worth $160bn across 3,000 online retail and travel businesses.

In retail, consumers using apps converted at a rate three times higher than those using a mobile browser, while in travel the conversion rate was almost two times greater.

As well as the growing importance of apps, the study found that some 40% of ecommerce transactions involved more than one device; smartphones, desktops and tablets were used in a variety of combinations to research and make purchasing decisions.

"The customer purchase journey has become increasingly complex as consumers have stopped using a single device to make their purchases," said Jonathan Wolf, chief product officer at Criteo.

"Delivering an engaging app experience and connecting seamlessly with consumers across multiple devices are key to capturing ecommerce sales in this new world," he added.

Globally, mobile is set to account for 40% of all ecommerce transactions by the end of 2015.

The figure for the US currently stands at 30% and Criteo expected that to increase to 33% by the year end. For top-quartile retailers, however, mobile is already at 40%.

Most retail categories have seen mobile grow in importance, notably health & beauty. Leading the way are fashion & luxury, followed by travel; only sporting goods saw a decline in the share of transactions taking place on mobile.

If the importance of mobile needed to be stressed further, evidence came in the conversion rates reported from mobile-optimised sites, which were more than twice that of non-optimised site, at 3.4% against 1.6%.

In fact, optimised sites had a better conversion funnel at all stages of purchase, with more products viewed per user (2.9 v2.3) and a higher add-to-basket rate (12.0% v 8.2%).

Wolf described the continued speed of growth in mobile as "astounding" and warned that "marketers' ability to leverage new technologies to accurately identify and reach consumers wherever they are is going to become critical".

Data sourced from Criteo, PR Newswire; additional content by Warc staff