Best Encrypted Messaging Apps in 2024: Signal, WhatsApp, Telegram, and More
Published on June 9, 2025 • 6 min read

The urgency to switch to encrypted messaging apps has never been clearer, especially after recent massive hacks targeting U.S. telecom companies. If you're a beginner wondering which messaging apps truly offer security and privacy, this guide demolishes the myths surrounding popular apps and breaks down the encryption protocols behind them. We’ll explore the encryption mechanisms used by Signal, WhatsApp, Telegram, iMessage, and a few honorable mentions like Threema and Wire. Whether you’re worried about government surveillance or hacker attacks, understanding how your messages are secured end-to-end is key to protecting your privacy.
Why Encrypted Messaging Matters: The Real Risks Behind Telecom Hacks
In 2024, a significant Chinese cyberattack, codenamed Salt Typhoon, shook the U.S. by exploiting vulnerabilities in telecom wiretap systems. These systems were originally designed for lawful interception by law enforcement with warrants. However, this breach revealed that the system itself was inherently flawed and easily exploited.
- Hackers accessed metadata like who contacted whom and when.
- In select politically sensitive cases, they intercepted actual message contents.
- The hack remained undetected for months, raising serious concerns about surveillance capabilities.
Following this, U.S. federal agencies banned unencrypted SMS and calls for official use, urging employees to move to encrypted platforms like Webex or Teams. The FBI also recommended the public switch to encrypted messaging apps, underscoring their importance in modern communication. For beginners interested, understanding how end-to-end encryption mitigates these risks is vital. Learn more about secure communication fundamentals in this official resource.
The Gold Standard: Signal and Its Robust Encryption Protocol
Signal is widely regarded as the gold standard in encrypted messaging, primarily because of its open-source Signal Protocol, which many apps like WhatsApp have adopted.
How Signal’s Encryption Works
Signal uses end-to-end encryption (E2EE), meaning messages are encrypted on the sender’s device and decrypted only on the recipient’s device, ensuring no middle party, including Signal itself, can access the message content.
- Signal employs the Double Ratchet Algorithm to provide Perfect Forward Secrecy. This means if a current encryption key is compromised, past and future messages remain secure.
- The Extended Triple Diffie-Hellman (X3DH) handshake establishes secure key exchange at the start of communication.
This layered cryptographic process dynamically changes encryption keys for every message, making interception futile.
Privacy Beyond Encryption
- Signal collects minimal metadata; it only stores the last login time and nothing about your conversations or contacts.
- It requires a phone number for registration, but recently introduced usernames to shield your number from contacts.
For a detailed dive into Signal’s protocol mechanics, the Demystifying the Signal Protocol blog is highly recommended.
WhatsApp: Secure But With Privacy Caveats
WhatsApp also uses the Signal Protocol, offering end-to-end encryption for messages. However, it’s owned by Meta (Facebook), which raises privacy concerns.
Differences from Signal
- WhatsApp collects more metadata, such as who you communicate with, when, your device info, and location data.
- Messages stored undelivered on servers can remain encrypted for up to 30 days.
- Being closed-source, WhatsApp’s server-side operations aren’t open to external audits.
Government Access Misconceptions
There are rumors that the CIA or FBI can access WhatsApp messages, but this generally refers to compromising your device, not breaking encryption. As Mark Zuckerberg clarified, encryption itself is solid, but spyware like Pegasus can expose messages on a compromised phone.
To learn more about WhatsApp encryption and privacy, visit WhatsApp’s official privacy policy.
Telegram: Popular But Not Fully Encrypted
Telegram is a favorite for many due to its massive user base and group features, but it doesn’t use end-to-end encryption by default.
Key Points About Telegram Encryption
- Messages are encrypted in transit, but not end-to-end encrypted unless you initiate a "Secret Chat," which is not enabled by default.
- Group chats and channels are not end-to-end encrypted.
- Activating Secret Chats involves multiple manual steps, which many users avoid.
Cryptography experts like Matthew Green doubt Telegram meets the industry standard definition of an encrypted messaging app. This perspective is detailed in his blog post Is Telegram Really An Encrypted Messaging App?.
iMessage and Google Messages: Platform Integration with Tradeoffs
iMessage
- Uses end-to-end encryption by default between Apple devices.
- However, iCloud backups are not encrypted by default; users must enable Advanced Data Protection for full security.
- Features are proprietary and closed source.
Google Messages
- Provides Rich Communication Services (RCS) which offers end-to-end encryption in one-on-one chats but not universally.
- Data collection and closed-source nature raise privacy concerns.
Both solutions offer convenience but with tradeoffs in metadata collection and potential access through cloud backups.
Honorable Mentions: Threema, Wire, and Session
For those seeking alternatives:
- Threema: Paid, open-source, no phone number needed, minimal data logging, good for privacy-conscious users.
- Wire: Open-source with end-to-end encryption, requires email or phone number, smaller user base.
- Session: Focuses on anonymity without phone numbers, offers strong encryption but lacks perfect forward secrecy.
While these apps have solid encryption, their smaller user bases limit practical communication reach.
Conclusion: Choosing the Right Encrypted Messaging App
When it comes to encrypted messaging, Signal remains the top choice for security and privacy, thanks to transparent protocols and minimal data collection. WhatsApp offers encryption but at the cost of more metadata sharing and corporate data policies. Telegram, despite popularity, falls short on default encryption standards.
Remember, encryption only protects messages in transit and at rest on servers. If an attacker compromises your device, even the best encryption won’t keep your messages safe. Considering your threat model and personal privacy needs is crucial.
Start by adopting Signal or similar open-source apps to enhance your communications privacy. For most users, switching to robust encrypted apps is a vital step towards digital security in an increasingly surveilled world.
If you found this guide helpful, take action today by downloading Signal or exploring these other apps to secure your messaging habits.
Meta Note: Throughout the article, images could be described, for example, visuals comparing app logos with metadata collection levels or infographics illustrating how the Double Ratchet algorithm advances keys per message.
Sources:
- EFF Secure Messaging Scorecard
- Demystifying the Signal Protocol
- WhatsApp Privacy Policy
- Telegram Encryption Analysis by Matthew Green
This blog post is based on content from a YouTube video. Watch it here. All rights reserved by the original creator.