For years now we've been drilling into readers' minds the importance of antivirus software, but times are changing and whereas previously many of their computing tasks took place on a desktop system they now take place on a phone or tablet.

Android viruses have hit the headlines before, leading users to think installing some sort of security software is a good idea. And it goes almost without saying: the more popular Android becomes the more of a target it is for the bad guys. But do you really need to install a resource- and battery-hogging antivirus app on your phone that is going to plague you with irritating notifications?

In almost all cases, Android phones and tablets do not need antivirus installed. Android viruses are by no means as prevalent as media outlets may have you believe, and your device is much more at risk of theft than it is a virus. But it is true: Android viruses do exist, and a decent antivirus app can provide peace of mind.

The vast majority of known Android viruses have been installed on the back of dubious apps - apps you will no longer find in the Google Play store. By default Android does not allow you to install apps from other sources, so there's no chance of you accidentally installing something nefarious.

Supposing a dodgy app does find its way into the Google Play market, Google will quickly pull the app and uninstall it from your device. But what if it comes back? Symantec has found at least seven malicious apps on the US Play Store that were pulled and then reappeared under new developers with new names.

If you are installing apps outside of Google Play, installing an Android antivirus app is one way to keep yourself safe. Our pick of the best is Bitdefender.

The worst thing you can do, however, is to assume you are protected by an antivirus app and drop your guard. Recent research by AVComparatives found that two-thirds of the 250 Android antivirus apps it tested do not actually work. So it will pay to be picky about which vendor you trust with your device security. Bitdefender, Kaspersky, McAfee, Avast, AVG, Trend Micro and Symantec all performed well in the research.

Even with the best antivirus apps, though, false-positive results are common. This means you may find your AV app reports an app as dodgy when it's actually harmless. In these cases, taking other precautions can be a more appealing way to safeguard your device from Android viruses.

Such precautions range from carefully checking any requested permissions before agreeing to them, avoiding cloned apps and keeping Android up to date (with all security patches applied).

You should also keep your wits about you, and apply a healthy dose of common sense. You wouldn't click on an attachment in a dodgy email from a sender you don't recognise on your PC or laptop, and we hope you would apply that same thinking to suspicious links sent in Gmail on your phone or via WhatsApp or Facebook Messenger. Typically, these type of links are associated with phishing scams, but that doesn't mean they won't install a virus on your device.

Supposing your Android phone or tablet does start acting oddly and you have reason to believe malware is at play: a factory reset is all that's required to get it back to normal (one reason why it's a good idea to always back up Android). But if you don't fancy wiping your device we have also issued some handy tips on how to remove an Android virus.

In many cases users report to us that they are seeing suspicious pop-up ads in their browser, or they are being redirected to a different home page to that which they configured in the settings. Our usual advice is to clear out the browser's data cache (in Settings > Apps & Notifications > Chrome > Storage > Clear Cache). You can also read more about how to block pop-up ads in Android.

It's worth pointing out that antivirus apps for Android often have other useful benefits, such as the ability to remotely lock or wipe a lost or stolen phone, or backup and cleanup tools. All these tools are available elsewhere - usually via free apps or manual administration - but for ease of use it can help to have everything in one place.