- Nine out of the top 10 messaging apps offer end-to-end encryption, but 90% now have AI tools that can reveal your private data.
- Signal ranks as the most private messaging app that uses quantum-safe cryptography and collects only your phone number.
- Meta’s Messenger and LINE rank among the worst offenders for aggressive data collection, collecting massive amounts of user information for advertising and tracking.
From sharing passwords with family members to venting about our bosses, we trust messaging apps with our most intimate conversations. But while we naturally assume our private chats will stay private, a disturbing new analysis reveals that your favorite app could be harvesting your data right under your nose.
A recent study by cybersecurity firm Surfshark took a magnifying glass to the 10 most popular iOS messaging apps in 2025. The researchers looked past basic marketing promises, examined encryption standards, data collection practices, and the creeping introduction of artificial intelligence features.
The good news is that basic security is becoming an industry standard. 9 out of 10 apps analyzed provide end-to-end encryption (E2EE)meaning that no one, not even the app developer, should be able to intercept and read your messages.
If you combine a secure messaging platform with a reliable VPN to encrypt your wider web traffic and hide your IP address, your daily communications are generally safe from prying eyes.
The bad news, however, is that aggressive data collection and poorly implemented AI integrations are quietly undermining these encryption efforts.
The best (and worst) messaging apps for your privacy
When it comes to treating your data with respect, the messaging market is sharply divided. Surfshark evaluated 35 specific data types listed in the Apple App Store to see exactly what these companies are scooping up.
The best: Signal
With an outstanding privacy score of 0.99, Signal easily takes the crown. It completely avoids user tracking and collects only one piece of data: your phone number.
Alongside Apple’s iMessage, Signal is also one of the only apps to offer quantum-safe cryptography, future-proofing your messages against next-generation cyber threats.
The worst: LINE and Messenger
At the other end of the spectrum, LINE is at the absolute bottom with the lowest privacy score. Both LINE and Meta’s Messenger are notorious for their data-hungry practices.
While the average messaging app collects 17 types of data, Metas Messenger collects a staggering 32 out of 35 possible data types.
Furthermore, 30 of these data types can be used for purposes completely unrelated to the functionality of the app, such as targeted advertising and product customization.
The laggards: Discord and Rakuten Viber
Discord stands out as the only app in the survey that completely fails to provide end-to-end encryption for text-based messages. Along with LINE and Rakuten Viber Messenger, Discord is also one of the few platforms that actively collects data specifically for user tracking.
The growing risk of artificial intelligence in your private chats
While encryption keeps hackers out, the widespread use of AI tools creates entirely new vulnerabilities. A dizzying one 90% of messaging apps analyzed by Surfshark now offer some form of AI integration.
Whether it’s a virtual assistant summarizing a long chat or an AI bot translating a message, these features require access to your conversation data. You’re not just talking to a helpful virtual friend; you send data directly back to the service provider.
Highlighting this threat, researchers from New York University and Cornell University warned in the Surfshark report that “AI capabilities are developing at a rapid pace, increasing significant security risks for users of E2EE applications”.
In the end, technology can only protect you so far. The FBI and the Cybersecurity and Infrastructure Security Agency (CISA) recently issued warnings about phishing campaigns that specifically target secure platforms like Signal.
If a hacker tricks you into handing over your login credentials, no amount of quantum-safe encryption will keep your contact lists and private messages safe.
Do you want to know more? You can read the full Surfshark report here
