Forget any bugging of your wheelie bin - if the Government / police / identity thieves / blackmailers really want to track you and your life then there's something slightly more to be worried about. It's with you all the time, it knows where you are and what you're saying. It's often linked personally to sensitive identity and financial information about you. You even pay heavily for the privilege of having it.

Yes, of course, it's your mobile phone.

Mobile phones these days are in many ways too damn clever. They're more like mini-computers in many cases, with a multitude of features and software available for them. Just like "real" computers, not all the software can only be used for lovely innocent purposes.

Imagine this: some cyberstalker wants to hear what you're up to, a continuous and portable transmission of your day to day life. In the bad old days what they might have to do is somehow place an invisiblish bug plus power supply on you, have a suitable receiver and follow you around all day. These days? They can simply transmit a program to your phone (not necessarily requiring them to even see you or your phone) that will turn on your microphone and use the standard phone transmission technology to forward all your private conversations and environmental sound effects to themselves. The program could be invisible to the average user and even work when your phone is ostensibly "off".

Paranoid realms of fantasy? Not really. Recently it came to light that the FBI has used exactly this technique, the terminology being "roving bug", against John Ardito and Peter Peluso, alleged members of an organised crime family in New York.

To quote from the Financial Times:

[mobile phone companies] can also remotely install a piece of software on to any handset, without the owner's knowledge, which will activate the microphone even when its owner is not making a call, giving security services the perfect bugging device.

This can only be done to certain phones. These guys used Nextel phones, but apparently Samsung and the famous Motorola Razr phones are especially easy to infiltrate with such software. Its use is restricted to authorised law enforcement only of course, and to the Poorhouse's knowledge has not been done without the consent of the mobile phone company involved, but it absolutely always pays to remember that not all the rich bored techno-genuises work for the Government. It is surely only a matter of time before someone somewhere works out how to do this, perhaps even on a mass scale, for entirely nefarious reasons. If it hasn't already happened.

With modern phones having data capabilities including picture and videocameras, perhaps it won't be too long before these can be set on covert transmit. Furthermore, it has long been known by the privacy conscious that you can be roughly tracked by simply having a mobile phone on your person which is turned on. Traditionally this is done via triangulation; working out your location by looking at the signal from several nearby phone-masts.

This technique was used recently by the UK authorities to track down Hamdi Adus Issac, a criminal suspect who had escaped to Italy only to be captured partly due to him turning on his mobile phone when he got over there. You can be tracked to around the accuracy of 25 metres apparently, but it will only get better / worse (depending on your viewpoint) as more and more phones which have super-accurate GPS receivers in them are purchased and used. We've all seen the adverts showing phones which can do satnav. If you want proof of concept, then there are already (legitimate) services that use this technology for reasons such as tracking your children or finding your friends.

The end point of all this is a situation where you are totally unaware that some weirdo is watching a live video feed of your activities 24 hours a day with your continuously updated geographic location pinpointed to the nearest metre.

So, how to defend yourself against such a possibility? Some choices:

• Don't take your mobile phone with you if you're up to something a bit private (the safest option)
• If you do, then take your battery out of it. Turning it off alone, whilst it used to defeat old-skool triangulation, may not any more if the phone has been programmed to fake the switch off
• Continually scan your immediate area and self for bugs
• Ensure your immediate area is shielded from outgoing transmissions. Clue: if you can make a phone call you haven't done this
• Keep an eye on the battery usage - if it goes down unexpectedly fast, this may be a sign of unauthorised transmission
• Get a phone that can't be programmed this way. The Poorhouse doesn't want to guess any specific examples of such a phone, but it's probably fair to say the rather more historic models are less liable to being capable of being hacked this way.
• Give up and accept that if someone really wants to monitor your every move they'll find a way whatever you do