But what about the phone in your pocket? Today’s handsets are fully functional mini-PCs with as much, if not more, processing power than the one on your desktop - so do they need an anti-virus app, too? The short answer is that it depends what sort of phone you have and how you use it.
iPhones operate within a “walled garden” cultivated by Apple itself, and software that does not meet a set of stringent criteria is not allowed into the app store and can not, in theory, find its way to your phone. It’s not a cast-iron guarantee of security, but for nine out of ten users it’s the next best thing
Google adopts a more relaxed policy to what it lets into its Android Play Store. Many apps contain quite aggressive advert-pushing techniques which can sometimes be disguised as desktop-style alerts that your phone is infected. These are harmless in themselves but taken at face value, they are annoying and, for some users, upsetting.
That doesn’t mean you should put your hand in your pocket and pay some nameless vendor for protection, however. There are plenty of free anti-virus apps available, for Android and iPhones, and it it’s peace of mind you’re after, any one will suffice. Look for names like Avira, Avast and Bullguard, but be careful to choose the free option. If you’re nagged to buy a subscription, uninstall and look elsewhere.
Remember that your phone can’t pick up a virus unless you accidentally install one - and if you spend your time browsing only mainstream websites and using the better-known apps, that’s unlikely to happen.
The bigger risk to security is not from a virus at all but your own carelessness. Phones are easily lost or stolen, and you don’t want someone else looking at your emails and texts, let alone your Amazon and bank login details. If the worst happens, those anti-virus apps will usually let you erase your phone remotely, by logging into a website - but you can do that anyway, using the phone’s native software.
On an Android phone, you can simply visit android.com/devicemanager from any computer, sign into your Google account, and so long as it’s still switched on, you’ll get a fix on your phone’s current location, accurate to a few metres. You can then ring it, lock it or erase it with a single click.
iPhones offer a similar solution, which Apple calls Find My Phone - but it relies on you having enabled it before your handset went missing. If not, it’s a case of changing your passwords - which is not a bad idea anyway, if you think you might be a victim of malfeasance.
It’s important to keep threats in perspective - the internet is awash with so-called malware, and the people who create it are getting ever more sophisticated at propagating it. But the anti-virus industry steers a fine line just the right side of operating a protection racket, and many of the threats you may have read about are no more than thinly-disguised adverts.
The bottom line is that for most people, phones carry exactly the same risk as your wallet or purse - which is considerably less than running a Windows PC.