Download apps only from official sources, for example, Google Play or App Store. By downloading programs from unverified sites, you risk getting malware. You may install a fraudulent app that looks exactly the same as the official one. Always check how many people downloaded the app. For example, if a banking app was downloaded only 50 times, don't install it.
Android
Note
The path may differ depending on the device model.
Install Google Play Protect, which regularly checks your apps and the device for security threats. To do this:
Go to Settings → Google → Security → Google Play Protect.
Enable the Scan device for security threats option.
iOS
Apple only allows you to install apps on iOS devices from its official App Store. All apps that are listed in the store are carefully checked for threats. According to the developers, it's impossible to download a malicious app from App Store (unless you did a jailbreak).
Update software on your device
Update the system software and apps on your mobile device regularly or enable auto-update. Manufacturers constantly monitor for bugs and vulnerabilities and release fixes that protect users from new types of attacks. For example, Yandex Browser has a built-in active protection system called Protect, which constantly updates its databases of viruses, malicious extensions, fraudulent sites, and other threats.
Clear your phone's memory
It's a good idea to regularly clean the system from unnecessary files, such as cache files or duplicate photos and videos. This improves the system performance.
Enable the screen lock on your device so that fraudsters can't use it and the device doesn't make calls, send messages, or make purchases without your knowledge.
Android
Note
The path may differ depending on the device model.
Use a PIN, password, or pattern to unlock:
Go to Settings → Security.
Click Screen lock.
Choose a screen lock method:
My phone supports biometric protection
Built-in fingerprint sensor.
Face recognition (the name and technology depend on the smartphone model).
Note
Biometrics is the most modern and effective way of protecting your device.
My phone doesn't support biometric protection
Password.
PIN code.
Pattern.
Note
A complex password consisting of letters and numbers is the most secure non-biometric protection method for your device. PIN codes and patterns are easily hacked.
iOS
Use a passcode and Touch ID or Face ID:
Go to Settings.
Tap Touch ID & Passcode (iPhone 5S and newer models) or Face ID & Passcode (iPhone X and newer models).
Tap Turn Passcode On or Change Passcode.
Set up Touch ID or Face ID following the instructions on the screen.
Turn off notifications on the lock screen
Texts, emails, messages from social networks and messengers, one-time codes for confirming bank transactions, and other notifications can be displayed on the lock screen. If you don't want other people to see your confidential information, disable notifications on the lock screen.
Android
Go to Settings → Notifications → .
Click Lock screen notifications.
Select Do not show.
iOS
Go to Settings → Notifications.
Click Show Previews.
Select Never.
Use two-factor authentication
Don't give other people access to your account (profile and Apple ID) even if you're completely sure that it's safe.
Turn on two-factor authentication. This is an extra security measure that ensures that only you can access your account even if someone else knows the password. To log in to your account, you will need the usual login and password and a one-time code that you receive by SMS or email.
What to do if you lose your phone
Many modern mobile devices have special apps that can help you find your phone by GPS. If you can't find it, quickly block and delete the data so that attackers can't use them.
Learn more about what to do if your phone is lost or stolen: