How to keep your messaging apps safer from hijacking and prying eyes

Messaging apps have become the main way many people talk to family, friends and even colleagues. That convenience also makes them attractive targets for cybercriminals and anyone trying to peek into private conversations.

The good news is that with a few simple checks and settings, you can make WhatsApp, Signal, Telegram, Messenger and similar apps far more resilient against account hijacking and casual snooping.

Why messaging accounts are such valuable targets

Criminals use hijacked accounts to trick contacts into sending money, sharing one-time codes or opening malicious links. Messages also often contain passwords, ID photos, travel plans and sensitive work information that can be abused long after a compromise.

Even if no one breaks in from outside, unlocked conversations on a shared or lost phone may reveal private details, relationship issues or financial data. Thinking of messaging apps as long-term records, not just quick chats, helps justify a slightly more careful approach.

Lock down the account, not just the phone

A phone PIN or biometric lock is essential, but it is not enough on its own. Messaging services often allow account recovery or web logins with just a text message or phone call, which can be intercepted or misdirected if your mobile number is taken over.

Most major apps now include their own extra lock. Look for settings like “Screen lock”, “App lock”, “Two-step verification” or “Registration lock” and enable them, ideally with a separate PIN or passcode that is not reused elsewhere.

Add strong account verification

Two-step or two-factor verification adds a second checkpoint when someone tries to register your number on a new device. With WhatsApp and Telegram it usually means choosing a six-digit PIN and adding a recovery email. Signal offers a registration lock PIN as well.

Choose a PIN that is hard to guess, avoid birthdays or repeating patterns and do not store it directly inside the chat you are trying to protect. A reputable password manager or a written record in a safe place is more reliable than memory alone for many people.

Watch for hijacking warning signs

Account takeover rarely starts with a dramatic alert. More often, it begins with a small, odd request or notification. One common pattern is a friend asking you to forward them a code “sent to your phone by mistake” or urging you to click a login link.

Another warning sign is your app suddenly prompting for registration codes without reason, or contacts reporting messages that you do not remember sending. In these cases, stop, review recent logins and contact friends through a different channel to confirm what is happening.

Be careful with backups and message history

Many services offer cloud backups of chats. These are convenient, but they may store messages in a way that is not as well protected as the app itself. In some ecosystems, backups may not be end-to-end encrypted by default.

Check how your chosen app handles backups and encryption. If you decide to use cloud backups, turn on any available encryption option and set a strong password or key. If you prefer maximum privacy, consider disabling automatic backups and regularly deleting older conversations you no longer need.

Limit who can find and contact you

Most messaging platforms include privacy options that control who can see your profile photo, status, last seen time and about information. Restrict these to “Contacts only” or similar, especially if your profile reveals where you live, work or study.

Also review who can add you to groups without permission and who can call you. Tightening these settings reduces spam, harassment and attempts to harvest your number through mass group invitations.

Look after linked devices and web sessions

Desktop and web versions of messaging apps are extremely useful, but they increase your risk if you forget to sign out on shared computers or devices you no longer use. Someone with access to that machine can sometimes read ongoing chats in real time.

Open the “Linked devices” or “Active sessions” section in your app and remove anything you do not recognise or no longer use. Make this a regular check, for example every month or whenever you change jobs or share a computer temporarily.

Think before sharing sensitive information

End-to-end encryption means only you and the recipient can read the contents of a message as it travels over the internet. It does not protect against a screenshot taken on their device, a compromised phone or someone looking over a shoulder.

Before sending ID documents, bank details, intimate photos or confidential work files, pause and consider the long-term risk. If possible, use features like disappearing messages, view-once media or password-protected file sharing, and confirm that the recipient’s device is not shared with others.

When to seek expert help

If you suspect that someone has full access to your phone, mobile number or messaging accounts, basic setting changes may not be enough. Contact your mobile provider to check for number transfers, and reach out to your organisation’s IT or security team if this touches work accounts.

For serious stalking, harassment or blackmail, local law enforcement, consumer protection agencies or specialist support organisations can advise on legal options and digital evidence. Do not try to confront or counter-hack the person involved, as this can escalate both technical and personal risks.