London's ban for spy bins highlights lure of big data to business The revelation that Londoners have been secretly tracked by high-tech recycling bins shines a light on the fast-growing commercial demand for consumer data - and raises questions about privacy in a digital age. A London-based marketing group called Media Metrica has been using a network of bins in the City to capture the unique identifier codes of nearby phones - logging more than 4m devices in one week. The company says it wanted to understand footfall around its bins, which display digital advertisements to passers-by, though it had written on its website about the potential for using the data to help companies predict "personal habits." On Monday the City of London Corporation, which looks after the financial district around St Paul's, told Media Metrica to stop the data collection and reported it to the Information Commissioner's Office. While its use of bins was novel, Media Metrica is by no means the only company to have been seduced by the power of mobile technology to collect data from consumers. Controversy blew up last month in the US after the New York Times revealed that dozens of retailers were tracking customers" movements by following the WiFi signals from their smartphones. Peter Cochrane, a futurologist and former chief technology officer at BT, said a similar thing was happening in the UK: "Some of the big stores now are offering people free WiFi. Good idea, good service, but believe me they will be tracking you, looking at which aisles you're in, where did you dwell, what did you buy, did you meet anybody. Data-mining by retailers is not a new phenomenon. Customer habits can be tracked so closely through loyalty schemes that Target, the US chain, is able to pinpoint when a customer is about to give birth - based on changed shopping patterns - even before they start buying nappies. Recently debate about privacy has turned to the online world: how websites and apps collect data about browsing habits and use it to deliver targeted advertising. But now the online and offline worlds are colliding as smartphones and wireless networks open opportunities to access consumers when on the go. "Big data is big business at the moment," said Peter Gooch, privacy practice leader at Deloitte. Many more industries that you wouldn't expect to monetise data are starting to do so. Companies are using data in increasingly sophisticated ways, matching online and offline behaviour. Tesco, the supermarket chain, this year started to tap its customers" shopping histories to sell targeted online advertising. Most of this data collection and analysis is legal and is designed to help companies and consumers by delivering more relevant adverts or products. However, privacy advocates fear that, if unchecked, mass data collection will be used in harmful ways. According to a survey by Ipsos Mori published on Tuesday, the majority of British people are worried about the way companies collect, use and share data. Just 38 per cent of respondents believed companies will keep their data safe, and 22 per cent were confident their details would not be sold on to other organisations. Mr Cochrane believes the "digital slime trail" that people leave behind them will grow and that this data will be collected and crunched by companies whether regulators like it or not. This is a path that we're on now and I don't think it's a path we can avoid.