/ Shopping, Technology

Shops are spying on you – but does it bother you?

Eye spying on you

Threatened by competition from online retailers, shops are introducing new technologies to find out more about you, the customer. Do you find shops analysing your behaviour creepy, or are you happy to accept it?

You may not realise it, but when you’re sifting through shirts to find the right size, or deliberating over which brand of shampoo to buy, what you’re doing is both fascinating and valuable to retailers.

That’s why new technologies that monitor shoppers’ behaviour are becoming more common.

What shops are doing

Your smartphone is a great source of information for shops. It’s constantly communicating with nearby phone masts and wi-fi networks, and in doing so it’s sending out unique IDs which some shops can pick up. They use them to measure how often you visit the store, how long you spend in there and how you move around. They can even track people who are just walking past.

Sign in to the in-store wi-fi, and shops can find out even more about you. Some in-store wi-fi providers track customers’ locations within the store, and cross-reference this with any demographic information you’ve provided. In some cases, the sites and apps you use over the wi-fi are recorded and fed back to the store.

Then there’s in-store movement tracking cameras. These can measure how many people are going in and out of a store, which areas of the shop you’re spending time in and for how long, and even the items you’re picking up off the shelf.

And some digital video screens showing adverts can scan your face and determine whether you’re male or female and which age bracket you fall in to, just by examining facial characteristics. Advertisers look at the demographic data for particular times and places, and use it to tailor the ads they show.

Creepy, or nothing to worry about?

To me, there’s something inherently uncomfortable about a camera tracking your movements or analysing your facial features, even if you’re not being filmed. But the solution shouldn’t be for shops to keep quiet about the tracking that’s being done.

We think it’s unacceptable for retailers and technology providers to say – as some did – that customers don’t need to know that anonymous data is being collected on them, or to hide the tracking they do deep within a privacy policy that customers are unlikely to read while out shopping.

Shops should be upfront about what monitoring they’re doing, explaining the benefits for customers and laying out how their anonymity will be protected – and where possible, they should provide a way for customers to opt out if they’re still not comfortable with it.

What do you think – does it make you uncomfortable to know that shops are analysing your behaviour? Or do you think it will make for a better shopping experience?


Which shops are monitoring GSM signalling? How do they match the phone’s IMEI number to the shop customer? They wouldn’t know the identity of a customer from a phone’s IMEI number. Only a mobile network would be able to do this. It sounds rather far-fetched.

I often use free wifi in many retail businesses, for example O2 and The Cloud. I realise that my visit to each business will recorded by my use of the wifi, but this is the price I pay for using the wifi, so I don’t mind.


May I give you a recent example… I went to a certain fast-food restaurant of an evening. The next day I was served with a survey from ‘Google Rewards’. I use an Android phone and use this App to earn a bit of money answering surveys. The survey asked me if I was in said fast-food restaurant at said time on said day. I didn’t answer, but Google/fast-food restaurant knew where I was.


Hi NFH – that’s correct, they wouldn’t know your identity from that number – however, they would be able to know how often the user of that phone visits the store, how long they spend in there and how they move around the store. A company called Path Intelligence uses this technology in around 40 shopping centres across the UK, though they wouldn’t tell us which ones specifically.


I wonder how clever these companies are with interpreting information about individuals. Will they manage to work out that I left without buying anything was because I did not appreciate having to listen to piped music? I hope so.


Something my mother and I love doing when we go past ridiculously expensive items in a department store is to point at the price tag and laugh with our mouths wide open holding our bellies, all silently and with exaggerated gestures, and then walk away, hoping that the CCTV cameras will pick us up. Now that we both finally have smartphones and after reading this article we’ll probably do that even more often.


This article on SpyBlog some years ago said Path were capturing TMSI — a temporary ID number assigned to your phone when it picks up a signal — rather than IMEI. Perhaps Matt has more recent information?


Might I suggest that when you pay for something that the proximity to a till and your payment card timing would work fine if they wanted to ID you.

BTW the second link takes you to an archived copy
Which? Archive
This article, Protecting personal details, was last updated on 30 July 2008 and is now out of date and held in our online archive for reference. Explore our latest Technology articles.


Thanks for spotting that one Dieseltaylor. I’ve removed it and added a different link further up the article. It’s about security tips when using public wi-fi so will be a little more useful. I’ve also added a link to the best and worst high street shops in the useful links section 🙂


Ever since Google Street View arrived it