The build-up of dirt, grease and germs on your tech kit is probably something you prefer not to think about, but it's important to clean your stuff regularly. See all PC reviews.
The reason, of course, is that we all clean our toilets with germ-killing bleach on a regular basis. But our computers and gadgets are rarely - if ever - shown a Jay cloth. Unless you are super-disciplined and always wash your hands before you pick up your iPhone or touch your laptop, you'll be covering them with germs.
And you can't rely on your own hygiene. If you let your kids or friends use your tablet or PC, they will probably leave a ton of bacteria all over your kit. There are even people who use their smartphone on the loo. Is it a wonder that they get sick?
As well as invisible germs, there's the all-too-visible grime that blights keyboards, screens and any other surface that gets touched. If you keep your smartphone in your pocket, the ports and connectors are likely filled with dust and other detritus which isn't just unsightly, it might cause problems when you try to charge or synch your device.
So how do you go about cleaning all your kit? Let's start with the humble PC, then move on to laptops, smartphones and tablets.
How to clean a PC or laptop
As well as the PC tower, you should also clean your mouse, keyboard and monitor on a regular basis. The PC's main enemy is dust, and fans quickly become covered in dirt and fluff if you have your PC under your desk. It's an even bigger problem if you have laminate or hard flooring instead of carpet.
Some PC cases have removable filters which are easier to clean than fans, but a quick vacuum of both (without removing the case) might be enough to eliminate most of the dust. Make sure your PC is turned off, naturally. Be careful not to hold you Hoover over a fan for too long, since spinning it too fast could damage it. You can insert a pencil between the blades to prevent them turning if you like.
If you're feeling more adventurous, you can remove the case's side panel (and even take out the fans) and clean them with a damp cloth. Make sure you check the CPU and graphics card fans while you're in there. Don't touch any of the other components inside the PC, though.
To clean those, invest in a can of compressed air to blast the dust off circuit boards and the internal panels. Try not to blow dust inside the power supply, and don't disassemble a power supply to clean it. You can then gently vacuum the bottom tray to get rid of the dust.
You can clean the outside of your PC using a damp cloth. If you want to try a detergent such as washing up liquid, or an anti-bacterial cleaner, test on a small area first to make sure it won't damage metal or plastic.
To remove dust any ports at the front or back, use the compressed air rather than a brush. Any static electricity could damage your PC.
How to clean your Keyboard
PC keyboards are relatively easy to clean. Disconnect yours and turn it upside down over a bin or a surface that's easy to wipe clean. Give it a few taps and be prepared for biscuit crumbs, eye lashes and other undesirable things to fall out.
As with the PC base unit, use a damp cloth to wipe dust and dirt off. Anti-bacterial sprays shouldn't damage plastic keys, but always test on a small area first. Don't drench the keyboard with liquid or you risk destroying it. Instead, spray the cleaner onto your cloth - not directly onto the keyboard.
If you want to spend some money to get the job done, try Moshi's Complete Cleaning Kit, which includes a reversible 'teraglove', a combined brush and micro-fibre tip 'pen', and a spray bottle which you fill with water.
It costs £15 from Apple and helps remove dust and grime between keys, while the glove is great for cleaning screens.
Laptop keyboards aren't quite as simple to clean as PC versions. First, turn the computer off, and remove the battery if possible. With the screen fully open, turn the laptop upside down and gently tap the dust and dirt into a bin or onto a surface.
If there's a problem with an individual key, perhaps because a large crumb is under it, you might be able to carefully prise off the key with your fingernail. Most laptop keys simply clip on, but never force a key or you risk breaking the clips or scissor mechanism.
How to clean your computer Mouse
Gone are the days of the ball-mouse - all use an optical sensor of some description now. Dust and dirt can easily build up over the sensor and cause tracking problems, so use a damp cloth to clean the entire bottom surface of your mouse.
The top is where you'll leave grease and germs, so it's wise to use an anti-bacterial spray. As before, check on an inconspicuous area first and spray onto the cloth, not the mouse.
If you don't want to risk any damage to your PC, keyboard or mouse, use a cleaner designed for electronic equipment, such as Muc-Off Device and Screen Cleaner (see below).
You can use Muc-off, or simply a damp cloth, to clean most PC screens (and TVs too), whether they have a matt or glossy finish. You can spray directly on to a screen, but don't let drops run down into the casing at the bottom.
A micro-fibre cloth is ideal for cleaning a screen as it helps to avoid streaks and is effective at removing dust and fingerprints. Use a damp micro-fibre cloth if marks are hard to shift, but be careful not to press hard on a PC screen as you can easily damage the LCD panel.
The rest of the monitor can be cleaned the same way as a PC tower or mouse, using an anti-bacterial spray if you prefer. As ever, don't spray any liquids directly onto the casing, as it could damage the electronics inside.
How to clean a smartphone or tablet
Touchscreens tend to be the most frequently cleaned component, since an accumulation of fingerprints obscures the image and feels nasty. However, it's crucial to use the correct cleaning products in order to avoid damaging your delicate electronics.
Most touchscreens these days have an oleophobic coating - literally 'oil fear' - which allows them to repel fingerprints. Such coatings aren't amazingly successful, but they are easily damaged by harsh cleaning agents such as ammonia, alcohol and other solvents.
For this reason, all you need to remove grease and dirt from your screen is a micro-fibre cloth. You can pick these up in a supermarket or online for next to nothing. Micro-fibre cloths are better than other material because the tiny, split fibres lift the dirt and retain it, as well as absorbing liquid. This means they don't leave lint on your screen, or simply spread the dirt around. You can dampen a micro-fibre cloth with water if the screen is particularly dirty.
When cleaning, use a circular motion rather than linear to a give an even finish and avoid the risk of long scratches if a large piece of dirt gets caught up in the cloth. You'll find that a micro-fibre cloth will also effectively clean the rest of your device, including metal and plastic parts.
For ports and connectors, use a dry brush - a small paint brush is ideal - to gently remove dirt. Don't use a can of compressed air, as the force is likely to damage the delicate components.
If grime is stuck in the speaker or microphone grilles, it can be tricky to remove. You could try using your vacuum cleaner, but use caution. Another technique is to use a pin to clear individual holes in the grille.
There are many cleaning kits available for smartphones and tablets, but they tend to be over-priced for what they are. Some include a miniscule amount of liquid and a small micro-fibre cloth; others provide the spray bottle, and you provide the water (such as Moshi's kit mentioned earlier).
What you should look for is a cleaner that will kill germs but is free from alcohol and ammonia. Examples include Whoosh! Screen Shine (£5 for an 8ml spray bottle - overpriced in our view), Eco Moist (£6.50 for a 50ml bottle and a micro-fibre cloth) and Muc-Off's Device and Screen Cleaner, which cost around £7 for a 250ml bottle, but is also available in 'Rescue' kits which include a cloth.
Alternatively, you could buy a UV steriliser. These tend to be used for cleaning beauty or pet-grooming products but can equally clean your smartphone, tablet or other small gadget. You simply pop your device in the drawer, leave it for 20-30 minutes each side and the UV light will kill all bacteria and viruses without any chemicals or liquids.
These aren't as popular in the UK as in America, but it's still possible to buy a steriliser from Ebay for around £30 that's large enough for smartphones and tablets with up to 7in screens (search for the Germix UV Sterilizer). Larger versions cost proportionately more.
Most people protect their smartphone and tablet using a case, so it's worth bearing in mind that you should clean that as well as your device. If it's made from plastic you should be able to clean it with a standard kitchen or bathroom disinfectant spray.
Some plastic cases (and screen protectors, for that matter) have an anti-microbial coating, and while its effectiveness is questionable, it's certain to be a better choice than a case with fabric on it. Fabric is difficult to clean and disinfect, and will also harbour bacteria. Our advice is to avoid such cases.