Modern smartphones based on Android are one of the most popular targets for cybercriminals. Every day, thousands of new malware samples are released online that can quietly steal your data, sign you up for paid services, or turn your device into a botnet. Users often notice strange behavior of the gadget, but cannot understand the reason: why the battery is discharged in a couple of hours or where strange pop-up windows come from.
Checking a phone for threats is not just running a single button, but a comprehensive analysis of the system state. Viruses have learned to masquerade as system processes or legitimate applications, making them difficult to detect. In this article, we will analyze all stages of diagnosis: from visual inspection of symptoms to the use of specialized software and resetting settings.
Ignoring signs of infection can lead to complete loss of confidential information, including access to bank accounts. Prompt detection problems allows you to minimize damage and maintain the functionality of the device without contacting a service center. Let's take a look at how to conduct a full check of your smartphone yourself.
Primary signs of device infection
Before installing third-party apps, you should pay attention to indirect symptoms. Malware often consumes CPU and RAM resources, which immediately affects performance. If your previously fast phone suddenly starts to slow down when opening simple menus or takes a long time to load, this is the first alarm bell.
Particular attention should be paid to energy consumption. Viruses, especially miners or spyware, run in the background 24 hours a day. This causes the battery to drain much faster than usual, even when you are not using the phone. Also, the device may become noticeably warm in standby mode, which is a clear sign of active background activity.
⚠️ Warning: If you see ads on your desktop or notifications that appear on top of other applications, this is a sign of aggressive adware. Do not click on such windows, as they may trigger the installation of additional malicious code.
Another sure indicator is an unexpected increase in Internet traffic consumption. Spyware constantly transmits stolen data to remote servers. Check the statistics in the settings: if an unknown application consumes gigabytes of traffic, it must be removed immediately.
Pay attention to the list of applications in the settings. Viruses often disguise themselves as system utilities with names like “System Update”, “Wi-Fi Service” or “Flash Player”, but have a low-quality icon or no icon at all.
Built-in Google Play Protect
The first tool you should use is Google's built-in scanner. It runs at the operating system level and has access to a database of all known threats. This method is the most secure, as it does not require installation of additional software and does not conflict with the system.
To start the scan, open the application Google Play Market. Click on your profile icon in the upper right corner of the screen. In the menu that opens, select Play Protection. Here you will see the security status of your device and the date of the last scan.
If the scan has not been carried out for a long time or you suspect the presence of threats, click the button Check. The system will scan all installed applications and compare their digital signatures with the Google database. If problems are detected, you will be asked to remove dangerous software.
It is worth noting that Play Protect may miss some new or little-known threats, especially if they are not distributed through the official application store. Therefore, the presence of a green security icon does not guarantee 100% cleanliness of the system, but eliminates most mass attacks.
Manual analysis of installed applications
Many viruses penetrate the system under the guise of useful utilities: flashlights, memory cleaners or simple games. Users often grant them access rights themselves, without reading the permissions. Manual analysis of the list of apps allows you to identify suspicious elements that were missed by the automatic scanner.
Go to Settings → Applications (or Application Manager). Please review the entire list carefully. Look for apps you didn't install or applications with suspicious names. Pay special attention to apps without icons or with an empty name field - this is a common sign of malicious code trying to hide.
Check the access rights for each suspicious application. If a simple calculator asks for access to your contacts, microphone or geolocation, this is a clear sign of spying. Also pay attention to the “On top of other windows” and “Access to special features” rights - viruses often use them to intercept control.
| Application type | Normal rights | Suspicious rights | Risk |
|---|---|---|---|
| Flashlight | Flash control | Contacts, SMS, Geolocation | High |
| Calculator | No special rights | Access to files, Internet | Average |
| Antivirus | Full access to the system | Sending SMS (paid) | Critical |
| Game | Storage (save) | Reading SMS, Calls | High |
If you find an application that cannot be deleted through the standard menu (the "Delete" button is inactive), then it has received device administrator rights. In this case, you need to go to Settings → Security → Device administrators, uncheck the suspicious app and only then delete it.
☑️ Checking a suspicious application
Diagnostics through safe mode
If the phone works It feels strange, but you can’t find the culprit among the installed apps, you should boot into safe mode. In this mode, the operating system starts only with pre-installed system applications, blocking all third-party software. This allows you to understand whether the problem is in the system or in the loaded app.
To enter safe mode on most devices, you need to hold down the power button, and then in the menu that appears, long-press your finger on the item Turn off (or Reboot). The system will prompt you to switch to safe mode - confirm the action. On some models Samsung or Xiaomi the procedure may differ, so it is better to clarify the instructions for a specific model.
After reboot you will see "Safe Mode" inscription in the corner of the screen. Use the phone for a while. If advertising banners disappear, brakes disappear and battery consumption returns to normal, then (the virus) is definitely in one of your installed applications.
⚠️ Attention: In safe mode, some functions may be limited. Don't be alarmed if widgets or some of the settings don't work - this is normal. The main thing is that third-party viruses are inactive in this mode.
Being in safe mode, you can safely remove the most recently installed applications or those that are suspicious. After cleaning, reboot the phone as usual to exit this mode.
What to do if the phone does not exit safe mode?
Simply restart the device in the usual way through the power menu. If this does not help, remove the battery (if it is removable) for 10 seconds and insert it back, or press the power and volume down buttons for 10-15 seconds to force a reboot.
Using third-party antiviruses
When the built-in tools are not enough, specialized antivirus solutions come to the rescue. There are many reliable products on the market from well-known vendors, such as Kaspersky, ESET, Dr.Web or Bitdefender. They use heuristic analysis that allows them to find unknown threats by behavior.
When choosing an antivirus, download it exclusively from the official store Google Play. Avoid sites that offer “hacked” versions of paid antiviruses - with a high degree of probability, such an installer will contain the very virus that you are trying to protect against.
After installation, run a full system scan. Modern antiviruses can also check Wi-Fi networks for security, analyze links in messages, and look for vulnerabilities in privacy settings. Regular updating of signature databases is critical for effective protection.
A third-party antivirus is most effective against Trojans and spyware, but it will not help if the virus has already acquired superuser rights (Root) and has infiltrated the system partition.
Remember that installing two or more antiviruses at the same time is not recommended. They may conflict with each other, considering the actions of the second app to be viral activity, which will lead to a significant slowdown of the smartphone.
Radical measures: reset to factory settings
If none of the methods helped get rid of the problem, and the phone continues to work incorrectly, the last and most effective option remains - a complete data reset (Hard Reset). This procedure deletes absolutely all data from the internal memory, returning the device to the “as from the store” state.
Before performing a reset, be sure to save important contacts, photos and documents to your computer or cloud storage. After the reset, it will be impossible to recover deleted files without special services. Make sure that the battery charge is at least 50% so that the phone does not turn off during the process.
To perform a reset, go to Settings → System → Reset settings (the path may differ depending on the shell). Select item Reset all data (Factory Reset). Confirm the action by entering your PIN code or pattern.
⚠️ Attention: After resetting, do not restore applications from a backup copy immediately. Use a “clean” phone first. If the problem returns after installing a specific application, it means that the virus “slept” in its backup copy.
In some complex cases, when a virus infects the system partition, even resetting the settings through the menu may not help. Then you need to reflash the device with full formatting of the partitions via a computer, which is best left to the service center specialists.
After resetting the settings, first of all, update the operating system to the latest available version. Security updates (Security Patch) close vulnerabilities through which the virus could initially penetrate the phone.
Prevention and rules of digital hygiene
The best protection against viruses is their prevention. Most infections occur due to the fault of users themselves, who download content from unverified sources. Avoid installing APK files from forums, file sharing sites, and dubious sites. Use only the official Google Play.
Regularly update the operating system and all installed applications. Developers constantly release security patches to close security holes. An outdated version Android is an open door for hackers.
- 🔒 Do not follow suspicious links in SMS and messengers, even if they came from friends (their accounts could be hacked).
- 🚫 Do not grant applications rights that are not necessary for their operation (for example, access to the microphone for a flashlight application).
- 🛡️ Use a strong password or biometrics to unlock the screen to prevent attackers from gaining physical access to the device.
Following these simple rules will allow you to avoid 99% of potential threats. The security of your smartphone is in your hands, and regular attention to detail is the best antivirus.
Can a virus remain after a factory reset?
In 99% of cases, a full reset (Factory Reset) removes all viruses, since they are located in the user memory section. However, if the malware has infiltrated the system partition (which requires root access) or infected the SD memory card, it may return. In such cases, formatting the SD card and reflashing the phone is required.
Why does the antivirus not find anything, but advertising pops up?
Often this is not a classic virus, but an aggressive component in a legal application (for example, in a free game or utility). Antivirus apps may consider such an application safe because it is signed with an official certificate. The solution is to remember after installing which application the advertisement appeared and remove it manually.
Is it dangerous to connect to public Wi-Fi?
Yes, it is a risk. Attackers can create a fake access point with the name of a famous cafe or airport. When connected to it, all your traffic may be intercepted. Do not enter passwords for banks and important services on public networks without using a VPN.
How to check your phone for viruses without the Internet?
Built-in Google Play Protect requires a network connection to update the databases. However, some previously installed antiviruses have local signature databases and can perform a basic scan offline. You can also use safe mode to identify problems based on system behavior.
Is it true that the iPhone also has viruses?
On Apple devices with unofficial firmware (Jailbreak), viruses are possible. On regular iPhones with factory iOS, viruses in the classical sense are practically impossible due to the closed nature of the system (“sandbox”). However, fraudulent sites and phishing pose a threat to users of any smartphone.