How to check your phone for viruses and malware, and remove them

Real malware on phones is less common than adverts for “virus cleaners” suggest, but it exists, mostly through apps installed from outside the official store and links in messages. Here is how to tell and what to do.

Warning signs

• Apps you did not install.
• Pop-up adverts outside any app.
• Battery or mobile data use that jumps for no reason.
• The phone is hot or slow when you are not using it.
• Messages sent from your accounts that you did not write.
• A strange charge on your mobile balance.

Slowness alone is often not malware. First read how to speed up a slow phone.

How to check

1. Look at the app list. Remove anything you do not recognise or no longer use.
2. Look at battery and data use in the settings and see which app is the heaviest.
3. Check permissions. An app that asks for more than it needs, such as a torch app that wants your messages, is a warning sign.
4. On Android, look for the built-in Play Protect scan in the Play Store settings. Use only the official store and the security scan that comes with your phone.

How to remove it

1. Uninstall the suspicious app. If it will not uninstall, look for a way to remove its administrator access first, or restart the phone in safe mode (the method differs by brand) and then uninstall it.
2. Update the phone and your apps.
3. Change your passwords from a different, clean device, starting with email and banking.
4. Check linked devices and logins on your main accounts and sign out of any you do not know.
5. Reset as a last step. If the problem continues, back up only photos and contacts, not apps, and reset the phone to factory settings: how to switch phones without losing anything.

On iPhone

iPhones are tightly controlled, so real malware is rare. Pop-ups in the browser are usually adverts or scams, not infections. Close the tab, clear the browser’s website data, update iOS and remove unknown profiles in the settings.

Be careful with “cleaner” apps

Many apps that promise to clean or speed up the phone are adverts themselves. Do not install one in response to a scary pop-up.

Stay safe

• Install apps only from the official store.
• Do not tap links in unexpected messages: how to spot phone scams.
• Turn on two-step verification for your accounts.
• Keep the phone updated.
• If you banked or paid on the phone while it may have been infected, tell your bank.