Android viruses are rare, but they exist. Almost exclusively installed via dodgy apps, the best way to avoid an Android virus is to keep to the secured confines of the Google Play store.
Should your device get lumbered with some malware, we will explain how to put it into Safe mode, if necessary remove the malicious app's administrator status and then uninstall the app.
If this fails a factory reset should remove the bug once and for all, though you would understandably prefer not to have to do so if your Android isn't backed up.
Before we begin, it's worth pointing out that your Android phone or tablet probably doesn't have a virus. What you're more likely to be seeing is an ad that wants to convince you the device is infected and that you need to download an app, or sluggish behaviour (in which case you should also check out our guide on how to speed up Android).
To prevent further threats, you might also want to install an antivirus app for your phone or tablet. You'll find our pick of the best in our round-up of the best mobile antivirus.
If your convinced that malware is at large, read on for instructions on removing it from your device. (Also see: How to remove iPhone viruses.)
Where do Android viruses come from?
The number-one way an Android virus finds its way on to your phone or tablet is on the back of an app.
This is true of all the biggest Android viruses to hit the headlines over recent years: Gunpoder, Ghost Trojan, Googlian and Godless all came to be in this manner, while Mazar sneaks in via a text message prompting you to download the Tor browser (guess what: you're not downloading the Tor browser).
More recently, Checkpoint has alerted Android users to the FalseGuide botnet malware, which gets on to user devices through dodgy walkthrough apps for Pokémon Go and FIFA found in Google Play, then turns them into silent botnets used for adware.
These apps get around Google's defences due to the non-malicious nature of their first component, says Checkpoint, but users should immediately be suspicious by their request for device admin permission, which should not be given to any app. This prevents the app being deleted from your Android.
Android viruses have various aims, with some running malicious processes on your device, some stealing your personal information and others downloading additional software, which may not always be malicious itself. Whatever they're up to, you don't want them there.
How to avoid Android viruses
• Don't install apps from outside Google Play unless you know what you're doing: This functionality should be disabled by default, but to check you can open your phone or tablet's Settings menu, go to Security, then ensure the Unknown Sources option is disabled
• Avoid cloned apps: 99 percent of the time you will be safe downloading apps from Google Play, but malicious code has been found within apps there. Avoid downloading what appear to be cloned apps from unknown developers, or apps that simply don't do what they say they do
• Check app permissions: No matter from where you are installing an app, check its required permissions before hitting Install. Never allow an app device admin permission, which prevents it being deleted. And does a video player really need to see your contacts? You can also check reviews online and browse the developer's website to see whether it's a genuine operation or cowboy business
• Keep Android up to date: The latest version of the Android operating system won't necessarily be available for your phone or tablet, but you should check that it is as up to date as it can be. Next time you upgrade, consider a brand that is known for its timely operating system updates (for example, Nokia). Check out our guide on how to update Android for further advice
• Install an antivirus app: You don't need to install antivirus on Android, but it can give you peace of mind if you're concerned about viruses, and the apps often have other useful functionality too. Be warned that Android antivirus is known to occasionally report false-positives, but if you know an app is okay you know an app is okay. Our favourite antivirus option is BitDefender, but there's also plenty of other options for mobile security software in this separate article.
How to remove a virus from Android
Put your phone or tablet into Safe mode. This prevents any third-party apps running, including any malware.
On many devices you can press the power button to access the power off options, then press and hold Power off to bring up an option to restart in Safe mode.
If this doesn't work for your device then you should Google 'How to put [your model name] into Safe mode' and follow the instructions.
When in Safe mode you'll see 'Safe mode' at the bottom left of the screen.
Open your Settings menu and choose Apps, then make sure you're viewing the Downloaded tab.
Chances are you will know when your device started misbehaving, and you can usually line that up with a new app you might have downloaded.
If you don't know the name of the app you think has infected your Android phone or tablet, go through the list and look for anything dodgy-looking or that you know you haven't installed or shouldn't be running on your device.
Tap on the malicious app (clearly it won't be called 'Dodgy Android virus', this is just an illustration) to open the App info page, then click Uninstall.
In most cases, this is all you need to do to remove the virus, but occasionally you might find the Uninstall button is greyed out.
This is because the virus has given itself Device administrator status.
Exit the Apps menu and tap on Settings, Security, Device Administrators. Here you'll find a list of any apps on your phone or tablet with administrator status.
Simply untick the box for the app you want to remove, then tap Deactivate on the next screen.
You should now be able to return to the apps menu and remove that app.
With the virus now off your Android phone or tablet, all you need to is restart the device to take it out of Safe mode.
Now that it's working correctly it's a good time to back up whatever important data you have stored on the device, and install an Android antivirus app to protect you from any future viruses that come your way.
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