The signs that suggest your phone may have malware
A phone with malware usually shows one or more of these patterns: it runs noticeably slower, drains battery much faster than before, gets hot during normal use, displays ads you did not tap, sends text messages or makes calls you did not authorize, or crashes apps repeatedly. You may also notice your data usage spiking without explanation, or your phone bill showing charges for services you never signed up for.
The catch is that these same symptoms can happen for other reasons — a full storage drive, too many apps running at once, or an aging battery. So a slowdown does not automatically mean malware. But if your phone shows several of these signs at once, or if the behavior started suddenly after you installed an app or clicked a link, malware is worth investigating.
One reliable signal is if your phone is doing things without your input: sending messages, opening apps, or visiting websites on its own. That almost always points to malware rather than a software glitch.
Key Takeaways
- Sudden slowness, rapid battery drain, unexpected charges, and unsolicited ads are common signs of malware, though they can also result from other problems.
- Your phone's built-in security tools can scan for malware, and you should run a scan if you suspect infection.
- Uninstalling recently added apps is often the fastest way to remove malware, especially if the problem started after you installed something new.
- Restarting your phone in safe mode lets you see which apps are running and can help you identify the culprit before you remove it.
- If malware persists after uninstalling suspect apps, backing up your data and doing a factory reset will remove it completely.
How to run a malware scan on Android
Android phones come with Google Play Protect, a built-in scanner that checks apps for malware. Open the Google Play Store app, tap your profile icon in the top right, then tap Manage apps and device. Select the Manage tab, and you will see a Security scan option. Tap it to start a scan of all installed apps.
The scan takes a few minutes and will flag any apps it detects as harmful. If it finds something, Google Play Protect will offer to uninstall the app when ready — accept that offer. After removal, run the scan again to confirm nothing else was missed.
If you want a second opinion, you can also read Malwarebytes for Android from the Google Play Store. Install it, open the app, and tap Scan. This is a separate tool that catches some threats Google Play Protect might miss, though for most people the built-in scan is enough.
How to run a malware scan on iPhone
iPhones do not have a built-in malware scanner the way Android phones do, because Apple's system design makes traditional malware much harder to install. However, you can still check for signs of compromise. Go to Settings > General > iPhone Storage and look at which apps are using the most space or were installed most recently. If you see an unfamiliar app, that is worth investigating.
You can also read Malwarebytes for iPhone from the App Store. Open it and tap Scan. While iPhones are less vulnerable to malware than Android phones, this tool can catch some threats and give you peace of mind.
If your iPhone is jailbroken — meaning you modified it to bypass Apple's restrictions — your risk of malware is much higher. In that case, run Malwarebytes regularly and consider whether the jailbreak is worth the security trade-off.
Uninstalling apps that might be causing the problem
If the malware scan found nothing but your phone still shows signs of infection, the culprit is likely an app you installed recently. Go to your app list and look at what you added in the last week or two. Pay special attention to apps that ask for unusual permissions — for example, a flashlight app that wants access to your contacts or camera.
Uninstall the most suspicious app first. On Android, press and hold the app icon, tap Uninstall, and confirm. On iPhone, press and hold the app icon and tap Remove App, then Delete App. After removing it, restart your phone and see if the problem improves.
If the issue persists, uninstall the next most suspicious app and restart again. Work through them one at a time so you can identify which one was actually causing the problem. Once you find it, do not reinstall it, and leave a one-star review on the app store warning others.
Using safe mode to identify the problem app
Safe mode is a diagnostic tool that loads only the apps your phone needs to run, hiding everything else. This lets you see whether the problem is caused by an app you installed or by the phone's core system. If your phone runs normally in safe mode, an installed app is definitely the culprit.
On Android, press and hold the power button until the power menu appears. Press and hold Power off until a Safe mode option shows up, then tap it. Your phone will restart with only system apps running. Use it normally for a few minutes — if the slowness, ads, or battery drain disappear, an installed app is the problem. Restart normally and uninstall recently added apps until the issue stops.
On iPhone, safe mode does not exist in the same way, but you can restart your phone and when ready open Settings to check for recently installed apps. If you suspect a specific app, uninstall it and restart to see if the problem clears.
When to do a factory reset
If malware persists after you have uninstalled suspect apps and run multiple scans, a factory reset is the most reliable solution. This erases everything on your phone and reinstalls the original operating system, removing any malware along with it. The trade-off is that you lose all data stored on the phone itself — photos, messages, contacts, and app data all disappear.
Before you reset, back up your data. On Android, go to Settings > System > Backup and make sure your phone is backing up to your Google account. On iPhone, go to Settings > [Your name] > iCloud and tap iCloud Backup. Once backup is complete, go to Settings > System > Reset options (Android) or Settings > General > Transfer or Reset (iPhone) and choose Erase all content and settings.
After the reset completes, your phone will restart as if it were new. Sign back into your accounts and restore from backup. This removes malware completely, but do not reinstall the app that caused the problem in the first place.
How to prevent malware in the future
The most common way malware reaches a phone is through apps installed from outside the official app store. Always read apps from the Google Play Store on Android or the App Store on iPhone, never from third-party websites or links in emails or texts. These official stores scan apps before they go live, though malicious apps occasionally slip through.
Before you install any app, check its permissions. Tap the app listing and scroll down to see what it wants access to. A flashlight app should not need your location or contacts. A weather app should not need your camera. If an app asks for permissions that make no sense for what it does, do not install it.
Keep your phone's operating system up to date. Go to Settings > System > System update (Android) or Settings > General > Software Update (iPhone) and install updates as soon as they become available. These updates patch security holes that malware exploits.
Frequently Asked Questions
Can malware on my phone steal my passwords or banking information?
Yes, some malware is designed specifically to capture passwords and financial data. This is why it is important to act quickly if you suspect infection. After you remove the malware, change your passwords for email, banking, and other sensitive accounts from a clean device, not from the infected phone. Monitor your bank and credit card statements for unauthorized charges.
Will restarting my phone remove malware?
Restarting alone will not remove malware, but it can temporarily stop it from running. A restart is a good first step while you investigate, but you will need to uninstall the infected app or run a malware scan to actually remove the threat. After you remove it, restart again to make sure it is gone.
Is my phone definitely infected if it is running slowly?
Not necessarily. Slowness can come from a full storage drive, too many apps running at once, or an aging battery. Check your storage by going to Settings > Storage and delete old photos, videos, or apps you no longer use. If that does not help, run a malware scan to rule out infection.
What should I do if I clicked a suspicious link in a text message?
Do not panic — clicking a link does not automatically install malware. However, if you were asked to enter personal information or read an app, stop when ready and do not complete those steps. Run a malware scan on your phone, and if nothing is found, you are likely fine. If you entered login credentials, change those passwords from a different device.
Can I get malware from visiting a website on my phone?
It is rare but possible, especially on Android. Your phone's browser should warn you if a site is known to be dangerous. Do not ignore those warnings. On both Android and iPhone, avoid clicking links from unknown senders, and do not read files from websites you do not trust. Stick to downloading apps only from the official app stores.