How to Figure Out If Your Phone Has Malware (2024)

Your smartphone is like a mini computer that fits in your pocket, so—just like your laptop—it's also vulnerable to malware. On your mobile device, this can often take the form of spyware, adware, or ransomware.

Unfortunately, it can sometimes be difficult to determine if your device has been infected. This is by design, since those behind the malware don't want you to find their software and remove it. That means it's up to you to look out for signs of troubling activity.

iOS vs. Android: Which OS Is More Vulnerable?

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Android is an open ecosystem by design, which has its benefits but also makes the operating system more vulnerable to malicious apps than Apple's iOS. Google has made progress here; a report from 2021 noted that bad actors have had to get more creative in order to get their malware-laden apps onto Android devices. But Trojan Horse dropperapps used to steal people's banking details still netted over 300,000 downloads on Google Play in just four months that year.

If you have an iPhone, you may be thinking that none of this applies to you. After all, the idea that Macs don't get viruses certainly extends to all other Apple devices, right? Wrong. It's true that iPhones are less likely to get malware than Android phones thanks to Apple's rigorous approval process, but it doesn't mean they are immune. In 2023, spyware was found on iPhones belonging to Kaspersky employees. An Israeli firm was also discovered to be using iCloud calendar to infect iPhones.

So regardless of what mobile operating system you're running, it's important to stay alert. You never know when a seemingly innocuous app holds a nefarious payload.

Signs Your Phone May Be Infected

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So how can you actually tell if your phone has been infected with malware? It's not always obvious, but here are some things to watch out for:

1. Pop-Up Ads That Won't Go Away

If you're suddenly seeing a lot of ads in a specific app—or even when no apps are open—you may be infected with adware. These annoying pop-ups can generate money from ad clicks, try to infect you with worse malware, or link to scam offers. Bitdefender recently found 60,000 Android apps on the Google Play Store were loaded with adware, so it's a fairly common issue. Whatever you do, don't click!

2. Unexplained Fees on Your Bill

Take a look at your phone bill or credit card statements and make sure you can account for every charge. If not, there's a chance you may be the victim of a scam called cramming, where unwanted services are added to your phone and charged to your phone bill. In the past, wireless carriers have been accused of looking the other way in some cases in order to pocket a percentage of the monthly rate, so the onus is on you to be diligent and catch any bogus charges.

3. Your Battery Drains Faster Than Expected

While batteries do degrade naturally over time, you shouldn't see a sudden shift in battery life with normal wear and tear. Malware may be hijacking your phone's components in order to perform background tasks, or even secretly play videos, resulting in the battery needing a recharge faster than expected.

4. Your Phone Is Overheating

Under normal circ*mstances, your phone should never be hot to the touch, but certain malware can overwork the internal CPU or charging mechanism. For example, the Loapi malware is capable of overheating—and even melting—your phone. If your phone is overheating, we recommend unplugging it from any power sources and turning it off. Left unattended, a hot phone can cause fires and even explode.

5. Your Phone Is Slower Than Normal

If your device has been hijacked, the malware may be overworking the components inside your phone and causing simple tasks to take longer than they should. Over the years, we have seen prank videos, Indian characters, software vulnerabilities, wallpaper, and text strings crash phones, but if yours is suffering from a sudden slowdown, and even crashing, malware could be the reason.

6. Dropped Calls and Poor Connections

An outgoing connection to a foreign server can interfere with your phone's ability to maintain a stable Wi-Fi or cellular connection, resulting in poor connection quality and frequent dropped calls. If other devices on the same Wi-Fi connection are working properly, and no one else is experiencing dropped calls, malware may be the culprit. (Poor call quality and invasive sounds may also be a sign your phone has been tapped, which is a separate issue.)

7. An Unexpected App Appears

Sometimes an app you download can be loaded with malware that installs additional programs. Take a look at your app list and make sure you recognize and want everything on the phone. If you find something unexpected, do not open the app.

How to Remove Malware From Your Phone

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You've examined your phone and found something suspicious, or you have one or more symptoms of malware. Now what? Here are some steps you can take:

1. Enter Safe Mode on Android

If you're on an Android phone, try safe mode. The process may vary depending on your phone maker, but most new devices require you to hold down the Power button, and then long-press Power Off until you get the option to enter safe mode. Similar to Safe Mode in Windows, this disables third-party apps on your phone so you can safely inspect anything out of the ordinary, remove any apps you think may be infected, then return to normal mode to see if the problem has been fixed.

To do this on an iPhone, your phone needs to be jailbroken, so it won't be a workable solution for most users. However, Apple has a feature called Lockdown Mode, which limits the device's functionality if you are being targeted by malware or hackers.

2. Scan for Viruses

If you can't find anything by yourself, it's time to enlist a good antivirus, especially if you're using an Android device. But don't download any free app with "antivirus" in its description. Many either don't work or are secretly malware themselves. Go with a trusted name in the security space, such as Bitdefender, Kaspersky, Norton, and McAfee, all of which have their own antivirus apps. We recommend investing in one, scanning for viruses, and allowing the program to remove any malware it finds.

3. Reset Your Device

If no other solution can be found to free your device from malware, your only choice may be to initiate a factory reset and start from scratch. This will wipe your phone clean and hopefully remove any malware in the process. If you have a backup of your phone from before it went on the fritz (and you should), you can try restoring from that point.

On an iPhone, head to Settings > General > Reset and erase the device. If you have a viable iCloud backup, you can follow our directions. Android owners may need to find instructions specific to their phone's manufacturer. For a Samsung device, open Settings > General Management > Reset > Factory Data Reset to get the job done. You can restore from a backup on Google Drive if you follow these directions.

How to Avoid Malware

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Malware is no joke. Avoid falling victim to an attack by being cautious about what you download. For instance, before you download anything, read reviews of the app carefully to make sure people are getting what's advertised, though be on the lookout for suspiciously high marks and repetitive reviews on no-name apps. It could be a pay-for-play situation. If an app presents you with an offer you might not have been expecting, or asks for personal information, think twice before handing it over.

You should also pay attention to the permissions you grant to your apps. As a general rule, you should only grant access to features you expect the app to need. If it's a messaging app, for instance, and asking to make phone calls or access your camera, that could be a bad sign. Android and iPhone users can access a permissions manager under their respective privacy settings.