Some time ago, police were the only ones able to locate mobile phones and they usually required a judge to authorise it. But not anymore. In United Kingdom, various web sites give you the opportunity to see the path a person has been following during all day and where is he at every moment.

How does this work? Base stations, the antennas which allow you to communicate wirelessly with your mobile, have a known location so, as your phone is associated with the nearest base station there’s a reduced range where you can be at that moment. The precision can even be increased with the use of multiple base stations to locate you, in a process call triangulation, where your location can be found with a precision of few meters.

How do I track someone? It’s really easy. You only have to visit World Tracker web site and register. Then  you’ll be able to track the mobile phone you want. OK, not that really easy, as this would be a serious breach of privacy. When you add someone to your list they are send an SMS asking for confirmation, once they answer to it you’ll be authorised to track that mobile.

But, what about the mobile of your spouse or your coworker. It’s probably really easy for you to get it for a few moments, add it to the tracking service, confirm the received SMS and delete it so they won’t know about it. And then, ta-dah, you can locate that mobile phone without them knowing. Hey, even better, you can see them in Google Maps.

In theory, these companies have to send reminders to that mobile at random intervals of time, but many times days pass without receiving these reminders, so we could track someone for a few days without their knowledge.

Scared, now? Yeah, me too. This does not only work in United Kingdom. Some time ago, a similar service was launched in Spain called Localízame. It works in a similar way, where people have to authorise you, and then you only have to send an SMS with their number and you’ll receive a reply with their location and even the accuracy of this location.

There’s no real solution to this problem. The only thing you can do is keep your mobile phone with you at all times or, if you are really paranoid, not having a mobile could be even better.