Last updated: December 2013
Mobile phones are effectively hand-held radio transceivers, which constantly search for signals from ‘cell towers’ or masts through which they connect to the mobile network. In order to work, mobile phones must remain in contact with the network using the strongest available tower signal.
In this sense, locating and tracking is fundamental to how a mobile phone works and to how network operators provide an effective service for their customers. By triangulating the phone’s signal using two additional towers, it is possible to locate a phone more precisely, accuracy can be further increased by combining the cell tower connections with GPS and WiFi signals.
Who wants to locate your phone?
Location services can be useful personal tools for people with smartphones. They improve the accuracy of map applications, enable geo-tagging of social media posts and can even provide alerts for location-based errands e.g. ‘get cash’ alert appears when you are within 100m of an ATM.
These are all examples of active location services, in which location information is sent from the phone at the subscriber’s request. Subscribers can turn these active location services off and on in the phone settings.
Location information can also be passively detected on a mobile phone by a third party. Sometimes this is done at the request of the subscriber via that third party. For example, applications exist that enable subscribers to locate lost or stolen phones through their WiFi signal (providing it is switched on) and their phone signal (providing it is on and connected to the network).
Similarly, companies such as MobileLocate, Creativity Software and Mobile Commerce offer services that can ‘find’ specific individuals through their mobile phone handsets. Legally these services require the consent of the ‘locatee’ to be located, meaning that parents cannot monitor their children without their children’s knowledge, or employers their employees.
Some passive location services, however, are operational without subscribers’ knowledge and without any clear indication on the phone handset.
An example is FootPath developed by Path Intelligence. This software uses strategically positioned devices to locate and track mobile phones within a shop or throughout a shopping centre, helping retailers to better understand customer browsing and purchasing behaviour and therefore optimise their layouts.
Shopping centres can also use this information to set rents for retail units, advertise events, as well as improve the siting of emergency exits and amenities. Path Intelligence claims that this kind of tracking is equivalent to the way online shops track customers’ movements and that FootPath simply levels the playing field for offline retail outlets.
The information gathered from mobile phones by FootPath are the unique numbers assigned to handsets by the network operator – the Temporary Mobile Subscriber Identifier or TMSI. They do not identify the user, their telephone number or the content of texts, phone calls or emails. This enables Path Intelligence to promote FootPath as gathering ‘anonymous’ data.
Mobile phones with WiFi receivers are also open to passive location services, otherwise known as WiFi ‘sniffing’. A recent high profile example of this concerned recycling bins installed in the City of London. These bins recorded information from nearby mobiles phones with WiFi turned on and used this to target the electronic adverts on the bins to specific passers-by. By sniffing WiFi across an area, these bins can track the movements of people/phones over time, learn their habits and enable advertisers to target particular individuals.
This kind of targeted advertising is already in use by mobile networks who use software such as AdvertWise (Creativity Software) or companies like Weve (a joint venture by EE, O2 and Vodafone) to send location-based adverts and offers to consumers when they are close to a certain ‘attraction’ (restaurant, shopping centre, theatre etc.).
What you can do
You can minimise the possibility of being tracked by commercial organisations in several ways. Firstly, turn off the WiFi receiver when you leave a WiFi zone and turn off all location services. If you want to avoid being located through your signal, you can turn this off manually or by switching your phone to ‘flight mode’ whenever possible.
Subscribers should be able to stop targeted advertising messages simply by texting STOP to a specified (free) number. If such messages continue even after you have requested them to stop, you should report this to Ofcom.