Services like Foursquare and Gowalla - and now Facebook "Places", which Dominique and Alex have written about this month - encourage people to submit their location so that others (e.g. "friends") can see when there are in the vicinity (e.g. to meet up for a coffee). Participation is encouraged through incentives such as designating an individual the "mayor" of a location that they visit more than anyone else.
Location information is also handed out in less visible ways. For example, many phones now "geotag" photographs with location information, which shows not only when but also where they were taken. And, obviously, the use of store cards places you at a store at the time of use.
Its early days for location services, so we don't really know the full implications of sharing this kind of data - but, as is the nature of these things, it's a one-way street. Once the data is out there, you can never be sure of being able to remove it in the future. Can you really be sure that your movements this month won't come back to haunt you in some unforeseen way in 2020? If the police knew that you were in the vicinity of a crime, are you sure that you innocence would be 100% respected in the absence of any other incriminating evidence? Personally, I'd rather not risk it. (This is the subject of the book Alex is currently giving away as a guerrilla sticker prize).
One of the characteristics of the web that has resulted in individuals broadcasting so much of their lives is the anonymity it affords. For better or worse, people have been expressing their views, safe in the (misguided) knowledge that the digital and physical worlds are separate realms. However, with the growth of geolocation, the two are colliding. Unless you take care, all those "distant" people on the internet may now be able to find you as you go about your day.
Once again, it's the ease and lack of transparency with which this information can be unknowingly handed over that is worrying. Imagine, for example, the following plausible scenario. A young woman on a dating site may be flirting with someone she's never met before. After chatting for a while, sharing all sorts of private insights, she takes an innocent snap and emails it to her new friend. If that photograph is unwittingly geotagged, she's just given her home address to someone she barely knows.
Learn how to control the geolocation capability of your phone and disable it (only re-enabling them for the short period you require them - e.g. when using a satnav app). GPS is a major drain on the battery anyway, so it's a win-win.
By Andrew Tait
Further reading:Location services pose huge security risks, USA Today.