What is mobile security?

“What is mobile security?” Think of it as cybersecurity for your mobile devices—smartphones, tablets, and laptops—to protect them and their sensitive information from hackers and scammers. Your device can become vulnerable every time you unlock it, log into your favorite app, or connect to an unsecured public Wi-Fi^® network.

Not taking mobile security seriously can have real-world consequences.

• If you don’t secure your device properly, scammers can gain access to steal your banking credentials, make unauthorized purchases, and even drain your accounts.
• By using unsecured public Wi-Fi, others on your network may be able to intercept some of your sensitive data, such as Social Security numbers, credit card numbers, and personal communications.
• In some cases, a hacker can install ransomware on your device to lock it down and take it over until you pay a ransom.

Your smartphone is especially vulnerable since you likely carry it everywhere and store lots of personal data on it. The good news? By using strong passwords, biometric authentication, encryption, and the AT&T ActiveArmor^® app*, you can better protect your device and help prevent yourself from becoming a statistic.

Why is mobile security important?

If you don’t follow proper mobile security practices, you put your sensitive data at risk, can fall prey to identity theft, and can experience large financial losses.

In the first quarter of 2025 alone, smartphone users experienced more than 12 million cyberattacks, including malware downloads, data breaches, and unauthorized access to apps, messages, and private data.¹ Cybercrime damages, for example, were “expected to reach $10.5 trillion annually,” in 2025.²

Anytime you use your device without the right protection, you can face an array of mobile security threats. Although they’re constantly evolving, it’s essential to know the most common ones.

Common mobile security threats

The most common mobile device security threats can harm your device and expose your personal information through malicious apps, links, Wi-Fi networks, messages, and more.

Malware and viruses

Malicious software (malware) can install on your device—often as a Trojan—malware that pretends to be legitimate. This gives hackers access to sensitive information. Once installed on your mobile device, malware may:

• Collect your private data
• Steal your identity
• Use your apps without authorization
• Damage your phone’s software
• Disable your device entirely

Viruses are a type of malware that attach to files and replicate, spreading to other files and systems. If you open an infected attachment or install a bad app, attackers can compromise your device.

Ransomware is a type of malware that infects your device through links, emails, or system vulnerabilities. The malware will encrypt your files, so you can’t access them unless you pay by a deadline. Sometimes, the cybercriminal will threaten to leak your info or permanently delete it.

Be cautious about opening any suspicious messages or clicking any links that you weren’t expecting.

Phishing attacks

Phishing attacks occur when scammers impersonate trustworthy contacts, like friends and businesses. These attacks usually happen over texts, calls, and emails, as scammers try to steal your login credentials (passwords and answers to security questions) and other sensitive data.

Scammers can even spoof caller IDs and numbers, making phishing an increasingly sophisticated (and damaging) mobile security risk.

If you receive an email from a trusted contact that doesn’t seem right, contact them directly to confirm. Also, don’t share personal information (Social Security number, bank account info, login credentials) in response to unsolicited requests.

Unsecured public Wi-Fi

While public Wi-Fi can be convenient, consider the dangers of unsecured Wi-Fi² networks before you connect. For example, when you join an unsecured public Wi-Fi network, hackers can use data interception to see network traffic.

In “evil twin” attacks, bad actors can create fake Wi-Fi networks that mimic legitimate ones to trick users into giving up their information.

Hackers are generally after personal information, banking credentials, and credit card numbers. When it comes to Wi-Fi security³ best practices, use a virtual private network (VPN) to hide your Internet Protocol (IP) address and encrypt your connection on that network.

It’s also a good idea to avoid sharing sensitive data on public Wi-Fi, such as shopping online and entering your credit card info or accessing your bank account.

[Read: Online shopping safety tips]

App vulnerabilities

It can be difficult to know how secure an app is because even legitimate apps can pose a risk if they collect and use your personal information. Some are malicious and only exist to steal your data and compromise your device.

Although many apps ask for permission to access your files, personal data, and more to improve user experience (UX), that data can fall into the wrong hands.

Avoid downloading apps with vague names or that ask for excessive permissions. Also, check user reviews.

Despite numerous security threats lurking out there, you can take security into your own hands—and it starts with how you log in.

Key components of mobile security

You can improve phone security to protect your data with essential on-device security and authentication features:

• Strong passwords – Create long, unique passwords with a combination of uppercase and lowercase letters, numbers, and special characters. Avoid common words or anything easy to guess like 1-2-3-4 or 0-0-0-0.
• Biometric authentication – Use face or fingerprint scans to verify your identity. These methods are more difficult for scammers to replicate. You can choose to use them to open and unlock your device or with certain apps like banking or social media.
• Multi-factor authentication (MFA) – You can combine several ways to access your device and data, including biometrics and one-time passwords (OTPs). Also, try authenticator apps to add layers of protection to secure your logins, transactions, and more.
• Personal Identification Numbers (PINs) – Set unique PINs on apps and accounts to stop thieves from accessing your information even if they get access to your phone. Pair them with your passwords and biometrics for stronger security.
• Remote data wiping – If your phone becomes lost or stolen, you can enable remote wipe to erase your data. You can do a full or partial wipe to prevent someone else from accessing your sensitive data.

Beyond on-device security and using the right authentication tools, you can take an even higher-level view of security to protect your data.

Application protection

Only download apps from official app stores. Ensure any app you download is from a trusted developer and is well vetted. Read current reviews to see if users have reported any security issues.

Network security

Hackers may be able to see your browsing activity and personal data—especially on public Wi-Fi. Use a VPN to safeguard your data on unprotected networks. One of the top VPN benefits is data encryption.

Encryption scrambles data so only someone with the key can read it. Use apps and services with strong, built-in encryption. That way, even if attackers intercept your text messages sent via end-to-end encrypted messaging apps, they can’t read them.

Operating system security

Manufacturers constantly improve mobile security, so keep your operating system (OS) up to date to fix bugs and patch vulnerabilities. Activate built-in security features and install anti-virus software for the safest mobile experience.

Improving mobile security can be as simple as:

• Using strong, unique passwords and reviewing them regularly. Change your passwords if you suspect they’ve been compromised.
• Turning on auto-updates to download and install software patches that help reduce the risk of malware, ransomware, and other attacks.
• Enabling MFA for stronger sign-ins.
• Reviewing app permissions to limit access to your personal data, such as disabling location or microphone access unless the app needs it.

Take proactive steps to protect your device before you experience a cyberattack, and you can feel safer and more confident doing your daily activities.

The need for ongoing mobile security awareness

So, what is mobile security? It starts with protecting your device by enabling strong passwords, using biometrics and MFA, and using a VPN and encryption to help keep your data out of the wrong hands. Strong network security and careful app vetting also boost your protection. Having AT&T ActiveArmor for 24/7 security helps.

AT&T ActiveArmor scans your device and the web for potential security risks. It offers a VPN for safer browsing and performs routine identity checks to help ensure your personal information isn’t circulating online.**

Protect your device and your data by choosing the right device and the right tools, including the AT&T ActiveArmor app, for a safer mobile experience.

Connecting changes everything, and we’re here to help keep you connected.
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¹ Anton Kivva, “IT threat evolution in Q1 2025. Mobile statistics,” Securelist by Kaspersky, June 5, 2025, https://securelist.com/malware-report-q1-2025-mobile-statistics/116676/.

² “Cybercrime In 2025: It’s Easier Than Ever To Hack. Newbies Gone Phishing,” Cybercrime Magazine, January 17, 2025, https://cybersecurityventures.com/cybercrime-in-2025-its-easier-than-ever-to-hack-newbies-gone-phishing/.

*Requires compatible device/plan and app download. Data charges may apply. Terms and restr’s apply. Details: att.com/activearmorapp

**Some mobile security features require advanced security for $7/mo. Auto renews monthly unless cancelled.