A small study suggests people who use their mobiles while shopping are more likely to make unplanned purchases.\nResearchers at Fairfield University in the US put 231 participants through a simulated shopping task, in which they watched a first-person video of someone walking round a supermarket, picking up items and placing them in a cart. They were also given a shopping list and asked to compare their list with the items bought in the video.\n \nThose using their phones \u2013 for purposes unrelated to shopping, like making calls, sending text messages, checking emails or listening to music \u2013 were the most at risk of deviating from a shopping plan. This included buying items not on their list, and forgetting items they had planned to buy\nEven if phones were used during only part of the shopping trip the effect was similar \u201csuggesting that in-store mobile phone use may consume attentional resources even after the phone is put away\u201d the researchers said.\n \nThe participants were also found to be somewhat in denial about just how distracting their smartphones were.\n \n"Our finding that phone use that is unrelated to shopping negatively affects shopping behaviour was in stark contrast to beliefs held by consumers. The vast majority of shoppers we asked thought that mobile phones did not have any negative effect," said the study\u2019s lead author Dr Michael Sciandra.\n \nThe authors of the paper published in theJournal of the Academy of Marketing Science stress that their work is based on a simulated shopping trip so further work will be needed to find out if the conclusions carry to a real life setting.\n \nThe results are nevertheless worth considering by consumers and retailers.\n \n"Mobile phones are quickly becoming the principal distractor for many consumers and they offer a unique form of interruption. Our findings may influence consumers' attitudes towards mobile phone use while shopping and persuade them to reflect on how these devices impact our lives, both positively and negatively," Sciandra said.\n \nAustralian shopping centre operators like Mirvac and Myer Centre have been rolling out free Wi-Fi to malls in recent years.\n \nThe free networks provide retailers with the personal data entered by visitors when they sign up for the service, which can feed into a customer database. The technology can also remember the anonymous MAC address of devices that enters a network, even if the user doesn\u2019t sign up for the Wi-Fi.\n \nThe Fairfield University study suggests another, more fundamental advantage to encouraging shoppers to use their phones \u2013 they might spend more.