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How to Prevent the Theft of Electronic Devices

The crime rate has been falling in the UK, from a peak in 1995. Similar trends apply in many other countries. The bad news is that, despite a reduction in household burglary, property theft overall – and theft from the person in particular – has remained high or even risen over the same period, with computer-related equipment being especially targeted. Needless to say, mobile phones are particularly sought after, but we’re guessing most would-be thieves wouldn’t turn their nose up at a top-of-the-range laptop or tablet either.

It’s a depressing irony, then, that although convenience while you’re out and about is the whole reason for using portable electronic devices, once your equipment is taken out of the home or office it becomes much more likely to attract the attention of criminals. What’s more, the consequences could be serious. Certainly, the cost of replacement of the hardware has to be considered – and even if it’s insured, you won’t necessarily be fully reimbursed for the loss – but this is just a start. The possibility of theft makes data backup even more important on a laptop or tablet than it is on a desktop but, unless you use a cloud backup or an external disk kept separately from the laptop, your data will only be secured once you get back home. Potentially, therefore, you stand to lose a day or more of work and information which – in the case of notes made at a meeting, for example – might be difficult to replace.

We also have to consider the fact that sensitive data could fall into the wrong hands. Finally, getting a replacement for a stolen item, setting it up, re-installing all your software and restoring your data will take some time. Unless you have a spare, therefore, you could be without a laptop or tablet for quite a few days and this could have a serious impact on your productivity. It’s common to believe that these problems always happen to someone else and are probably due to carelessness.

However, one in 10 laptops is stolen during its lifetime and half a million people in the UK had a phone stolen in 2016. If these statistics have convinced you that this is a subject that can affect us all, do read on because, as you’ll see, a small change in your behaviour and a modest investment in anti-theft products could make your equipment a whole lot more secure. We’re going to be looking mainly about prevention of laptop theft here but some of the products, and most of our advice, applies equally to tablets, smartphones, cameras or just about any other electronic equipment you might want to use on the move.

Get the Right Product

Just as there are several ways of protecting your home or car from theft, the same applies to your laptop. The choice is even more diverse, however, so a bit of guidance is called for. Anti-theft products that are suitable for high-tech gear fall into three main categories.

First are products that make it physically difficult for a thief to get away with your gear – we can think of these as the equivalent of the lock on a door. Second are those devices which will draw attention to a thief should they attempt to steal your equipment; this is the equivalent of a household burglar alarm. And third are products for marking your kit to improve the likelihood of it being returned if it is stolen while, at the same time, making it less attractive to a would-be thief. Again, very similar products are available for household items. Here we’ll look at each category in turn, examining their pros and cons and highlighting some actual products. First we need to make an important point, though: no single type of product is better than the others and each offers benefits in certain circumstances. So, just as it’s common to have locks on your house doors and a burglar alarm, it would be wise to consider protecting your portable gear with at least two, if not all three, types of products.

Physical Anti Theft Kits

Most laptops have a so-called Kensington lock slot which is used to secure it using a security cable from Kensington or other manufacturers. The cable is wrapped around some immovable object such as the legs of a desk, then the end is threaded through a loop in the cable before being inserted into the Kensington slot. The laptop is now secured against casual theft, although it won’t deter a thief equipped with a pair of bolt cutters or who is prepared to damage the laptop to release the security cable. The laptop can be removed by its rightful owner using either a key or a combination lock, depending on the specific product. Prices vary significantly, from as little as £3 to over £35. Tablets rarely, if ever, have Kensington lock slots and smartphones are never equipped in this way. Realistically, it’s probably easier to just make sure that phones are always kept in a secure place, and any adaptor would be quite intrusive on such small devices. Nevertheless, if you’re willing to accept a bulge on the back cover, cable anchors that glue onto the back of smartphones are available from various sources and these can also be used on tablets.

However, a better solution for tablets is the Blade Universal Lock Slot Adaptor provided by Maclocks. This is a low-profile hinged bracket that can be attached to the base of tablets using high-strength adhesive, which allows a security cable to be attached, and that folds away when not in use. It costs around £38.


The first type of alarm we’ll look at, the Lock Alarm Mini at £25, serves a dual purpose in also providing physical protection. Like security cables, this product also incorporates a steel wire that is fitted to any type of product that has some sort of loop through which it could be threaded. For a laptop, you also need an adaptor which allows it to be fitted into a Kensington lock slot. The wire is much thinner than Kensington-type security cables but it probably won’t succumb to small wire-cutters and, in addition, its small diameter allows it to be retracted into the body of the unit when not in use. Where it differs from a plain security cable is that a 100dB alarm will sound if the cable is cut. A movement sensor can also be activated.

The next type of alarm, and one that is becoming increasingly popular, is the proximity alarm. These generally take the form of a Bluetooth-enabled tag that is attached to the equipment being protected and is paired with a smartphone. There are lots on the market, each with slightly different features, and although this isn’t a comparative review, we will indicate what to look for and approximately how much you can expect to pay. First, it’s important to recognise that the tags tend to be in the region of 35mm across and cannot easily be attached to a laptop. They’re frequently shown hanging from keyrings but they could readily be attached to a laptop case or hidden in one of its pockets. To truly be called a proximity alarm, an audible alarm should sound if the phone and the tag are separated by more than some preset distance. Not all tags offer this useful feature, perhaps because it’s tricky to gauge distance from Bluetooth signal strength.

What they do all offer, however, is a means of manually triggering an alarm on the tag from the paired phone if the tag is still within Bluetooth range – up to several tens of metres, depending on the device and whether there are walls between the tag and the phone. This helps you to track down the tag and might cause a thief to abandon it if it truly has been stolen. Many also have a crowd-finding facility which, even without people’s active participation, employs the user community to help find a device if it’s out of Bluetooth range. In reality, this isn’t going to be much use unless you’re in a densely populated area and you’ve chosen one of the most popular brands.

These products are equally effective against accidental loss as against theft, and to help you here, most associated apps will allow you to see, on a map, where your tag was last detected. Tags cost from about £20, but some have batteries that cannot be recharged or replaced so you have to buy a new tag – often at a reduced price, fortunately – after the year or so it takes for the battery to run down. The product family that is probably the market leader is Tile although, as yet, it doesn’t feature a true proximity alarm. The PebbleBee Honey is one that does offer a proximity alarm, also known as geofence, functionality. The other main type of alarm that’s relevant to laptops is the purely software version. These are really only effective against opportunistic theft and will sound if, for example, the mains power supply or a mouse is unplugged from an unattended laptop.

Unfortunately, pretty much all of these alarms only work on Windows and, while a few free packages are still available for download, most commercial products have been discontinued. However, for those proficient in coding, a DIY solution could be a possibility.

Marking Products

Products for marking equipment serve two quite distinct purposes. First, they improve the likelihood of your equipment being returned to you if it’s stolen and subsequently recovered by the police. Second, because possession of marked equipment could be discriminating, it makes your laptop or other equipment a much less attractive target to a potential thief. Two categories of product achieve these two important functions.

The first category allows you to mark a product in a way that is highly visible and difficult to remove. One type comprises stencils, prepared with either your address or a unique serial number, that are supplied with an applicator and special ink. The ink etches into the surface of your laptop or other equipment, thereby making its removal almost impossible. The other main type involves specially prepared tamperresistant labels, again showing your address or an ID, which are supplied with an adhesive for attaching them to your equipment. Again, removal is difficult and, at best, will leave tell-tale signs. When a serial number is used as opposed to an address, this product is sold with registration to a database – accessible by the police – that associates the owner with the equipment. The advantage this offers is that equipment can be re-registered if you sell it. Retainagroup offers this type of product in the UK, and STOP offers it in the US.

At first sight, the second category of products – those that mark your products invisibly – seems a strange concept. Some companies sell invisible ink pens that you’d use to write your postcode or ZIP code on your equipment, which becomes visible if you shine an ultraviolet light on it. We don’t recommend this solution since it offers no deterrent value and is also potentially removable with a solvent if the thief discovers the marking. Where things get more interesting is when we consider those products such as SmartWater, which is an invisible ink, prepared with a formulation unique to each customer, that you apply to the equipment and is almost impossible to remove completely. It can be detected with an ultraviolet light, leading the police to forward recovered equipment to SmartWater for analysis to reveal the registered owner. It’s provided with warning labels that you can attach to marked equipment, thereby providing that all-important deterrent value. SmartWater is sold in the UK; prices range from £25-35 for products in the Home Security range and these can be purchased from In the US, up to ten items can be protected foras little as $5 per month – see for details.

Behavioural Changes

Physical protection, alarms and marking products are important anti-theft measures and should be seriously considered by anyone who regularly takes valuable equipment outside the home or office. However, your behaviour is also important and changes here could prove to be equally as effective in preventing loss.

Our first piece of advice is to not advertise the fact that you’re carrying valuable equipment when you’re not using it. When you’re walking down the street, keep small items such as phones in your pocket or handbag rather than in your hand, where they can be easily seen and could readily be snatched from your grasp. Needless to say, this isn’t feasible with larger items such as tablets and laptops. However, it’s not necessary to carry them in a conventional laptop case, which does little to disguise the expensive equipment it contains. A police Crime Prevention Officer we spoke to said that he always carries his laptop in a scruffy supermarket bag because nobody would guess it contained anything more valuable than a few cans of beans.

If you want something a bit smarter, or that provides more protection from knocks, you could consider a backpack You could use an ordinary backpack of the sort you might take on a hike, but a special laptop backpack might be more appropriate, because they’re designed to hold a laptop of a particular size and have plenty of compartments for accessories and documents. You can easily pay over £100 for such a backpack, but we recommend opting for a much cheaper one so it’s not as conspicuous. These are widely available from several suppliers. With laptop backpacks now fairly common, their stealth value is not as great as it once was, but a thief will still find it more difficult to take a backpack from your back than a case from your hand.

Next, think about the situation when you’re using your equipment, most notably your laptop, in a public place such as an airport lounge, railway station, coffee shop or university library. It would be rare for a laptop to be stolen while you’re actually using it, although you should be careful about leaving a phone in view. After all, it only takes a momentary lapse in your attention for someone to walk off with any such small items. The main risk to your laptop, however, is if you need to take a break, perhaps to buy a coffee. It’s important to recognise that your insurance company might not reimburse you if leave your laptop unattended – and if it belongs to your employer, you might find yourself having to answer some very difficult questions from your boss.

Of course, the safest piece of advice that we can give is to never leave your laptop unattended, even if you only intend to be away for a very short time. That’s not always possible though, even if you just need a short trip to the loo, and in any case you might not want to appear neurotic (Looking neurotic is better than losing your laptop, but we have to be realistic). This being the case, how about carrying out a risk assessment to come up with your own set of rules?

You might decide, for example, that you will never leave your laptop unattended in an airport, on a train, or in a coffee shop or bar (and that really is the only sensible option in these places). If you’re in the university library, you might decide that you’d be prepared to ask someone to watch it for you, as long as you’re not going to be away for more than two minutes. This is also an instance in which you might decide to use a software alarm, bearing in mind that it’ll only provide a minimal degree of protection.

DIY Solutions

If you’re a developer as opposed to a user, you might want to consider creating your own anti-theft utilities and devices. We’ve already seen that software-only laptop alarms are few and far between and most of those that do exist only operate under Windows. Still, there’s some benefit in having an extra layer of protection, even if it’s not 100 per cent effective. So how about writing your own alarm? Since this will cost you nothing at all except your time, it’s worth considering.

The advantage in writing your own alarm is that you can decide exactly how you’d like it to operate. Be prepared to be innovative. Some features, such as sounding if the power supply is unplugged, are surely essential, but there are other useful things you might choose to add. For example, you might find that certain patterns of Wi-Fi signal strength are indicative of the laptop being moved, as opposed to someone just walking between it and the access point. If so, this might provide a means of detecting theft of your laptop, even if it wasn’t connected to mains power.

An alternative is to detect motion directly. While nearly all smartphones contain the accelerometers that would permit this, they are not nearly as ubiquitous in laptops. Some products, most notably Lenovo ThinkPads, have accelerometers as part of the Hard Drive Active Protection System (HDAPS) which parks the disk drive heads to prevent damage to platter if the laptop is dropped. Another example are convertible laptop/tablets that often include an accelerometer so that screen rotation can be detected. Finally, don’t forget that an alarm could be disabled just by turning off the laptop or closing its lid, so do be sure to disable both the power and the lid switch whenever the alarm is active.

Another DIY project you might want to attempt is a proximity alarm based on a small single board computer with an associated Android or iOS app. The Particle Photon would be a contender due to its small size and, while it isn’t much cheaper than an off-the-shelf Bluetooth tag, it does offer some benefits. First and foremost is the fact that you can add whatever features you want, rather than being constrained by what’s on offer in commercial products. In fact this additional functionality needn’t be restricted to theft prevention. These tiny SBCs are often targeted at Internet of Things applications, so you could use it to experiment with real-world monitoring too.

On the downside, many of the smaller SBCs – the Particle Photon included – have Wi-Fi rather than Bluetooth. For a tag that has to operate on internal batteries for perhaps a year or more, this would be a serious disadvantage as Wi-Fi is much more power-hungry than Bluetooth. If you’re going to run your tag from an external battery and are prepared to recharge it periodically, however, this is no longer a disadvantage, and has the extra benefit of a greater range.

Another platform that’s designed specifically as a tag, is the open source RuuviTag. This takes the form of a compact circular board powered from an onboard button cell, housed in a round waterproof case, fitted with various sensors including an accelerometer, and including Bluetooth. It costs roughly £76 for three units.

You’ll never find a solution that allows you to keep your laptop completely secure all of the time – accidents can happen – but you can do your best to minimise the risk of theft.

Published on Tue 29 August 2017 by Gary Hall in Security with tag(s): physical theft