7 secure messaging apps you should be using

You might want to rethink your favorite messaging app and opt for something more secure.
Person on a New York City subway train texting on their phone.
You have a lot of options when it comes to choosing among the most secure messaging apps. Ketut Subiyanto / Pexels

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When choosing a messaging app, it’s easy to just fall in line with whatever your friends and family have on their phones. Whether or not the platform is secure isn’t often a major factor in the decision. But maybe it should be, given the sheer amount of sensitive information we share with our contacts every day.

Not all messaging apps are the same, especially when it comes to your privacy and security. If you’re in the market for a more secure messaging app, we can help. The web is wide and diverse, and there are plenty of platforms that will satisfy your texting needs without asking you to disclose everything about yourself. It’s just a matter of looking.

You’ll be on your own when talking everyone else into moving to another platform, but we believe in you.

Signal

The gold standard of secure messaging apps, Signal is a stripped-down platform designed to put privacy and security first. In fact, the app’s protocol, developed by Open Whisper Systems, is also embedded within the code of competitors such as WhatsApp and Skype, and inspired Viber’s customized version.

Signal is free, open-source, and operated by The Signal Foundation—a non-profit with a mission to “develop open source privacy technology.” Brian Acton, one of WhatsApp’s founders, left Facebook (reportedly on bad terms) after the company acquired his platform, and donated $50 million to create the foundation. It’s one of the main reasons users trust the app, as there’s no big tech company behind it.

The platform supports texting, video and voice calls, as well as file-sharing. Privacy-wise, you can set your messages to self-destruct at any time from one second after they’re read to four weeks after you send them. End-to-end (E2E) encryption protects everything you share through Signal by default, and the foundation says it doesn’t store any sensitive information. The US government subpoenaed user data in 2016, but authorities only got their hands on the dates accounts were created, dates of last connections, and phone numbers.

Of course, handing over a phone number to create an account—and automatically sharing it with anybody who might find you through the app—means you won’t be entirely anonymous. Signal’s developers say they’re thinking of a way around it, but as of writing, there’s no date or specific project in the works to resolve this.

Still, Signal does its job well, and as more people get on board, it’ll be easier to keep in touch with your loved ones without anybody snooping around.

Signal is free for iOS, iPadOS, Android, macOS, Windows, and Linux.

WhatsApp

WhatsApp got a bad rap in 2021 when Meta, its parent company, announced a controversial update to the app’s privacy policy that would allow it to share information with Facebook and Instagram. People did not like it, and WhatsApp hit the pause button. The platform stopped sending notifications promoting the new privacy policy, and those who didn’t accept it have been able to continue using the app with no problems.

Sketchy privacy practices aside, WhatsApp is a versatile messaging app that’s fully end-to-end encrypted. The app supports text and voice messaging, voice and video calls, and sharing images, videos, documents, and other types of files. The platform has kept up with contemporary privacy and security features too, adding disappearing messages and the ability to entirely delete messages from private and group chats.

[Related: The 7 best apps for all your group chats]

WhatsApp also supports group chats with up to 1,024 members. The platform had a higher limit in the past, but that turned into a problem when the app became an effective tool for the propagation of misinformation and other illegal material. As a result, WhatsApp eventually limited the ability to forward messages and the size of group chats.

It’s unclear whether Meta will persist with its plans to integrate WhatsApp’s operation more intimately into the rest of its platforms, but the messaging app today enjoys the trust of more than 2 billion users worldwide, so you definitely won’t run out of people to talk to. 

WhatsApp is free for iOS, Android, macOS, and on the web.

Telegram

Telegram got its day in the sun when WhatsApp’s ill-received privacy policy announcement directly resulted in Telegram’s user base growing. The app reached 500 million users that year and has continued to grow, reinforcing its fame as a top-tier secure messaging app.

The app supports texting, voice and video calls, public channels, and file-sharing, with an interface highly similar to WhatsApp’s iOS appearance, so switching over from Meta’s messaging app should be seamless.

The platform also uses E2E encryption, but not by default. Only Secret Chats, which are one-to-one, are protected by this protocol. These chats leave no trace: they cannot be forwarded, leave no trace on Telegram’s servers, and you can have sent messages self-destruct after a specific time. This is great from a privacy standpoint, but it also means that all other communications (group chats, channels, and non-secret chats) are cloud-based and encryption protection ends when they hit the server.

[Related: Bring your WhatsApp stickers with you to Telegram]

The lack of widespread E2E encryption is meant to give users instant access to backups on multiple devices, no matter when they joined a channel or group chat, Telegram says. Pavel Durov, one of the app’s founders, also argues that government agencies might target users using “niche apps” such as Signal, assuming that anyone opting for that high level of privacy has something to hide. Having less-secure encryption as the default, Telegram says, protects users from unwanted surveillance.

As opposed to WhatsApp, which uses third-party servers like iCloud or Google Drive to store backups—giving Apple and Google the ability to manage that information—Telegram’s backups are broken into pieces and live on its own servers around the world. It claims chats, no matter what type, are all secured the same way, but because Telegram technically also has access to the encryption key, they can decrypt your messages… even if they say the key and the data it decrypts are never in the same place

Even though Telegram emphasized its commitment to security by updating its privacy policy to protect the identity of Hong Kong protesters in 2019, that commitment should be taken with a grain of salt, according to Gennie Gebhart, acting activism director at the Electronic Frontier Foundation.

“Telegram doesn’t have a great track record of responding to high-risk users,” she says. “My impression is that a lot of Telegram’s ‘secure’ reputation comes from its association with the Hong Kong protests, but the app was also useful in that environment for a lot of specific reasons, like no phone number requirement or the support for massive groups.”

That last feature, which allows users to create chats that can impressively host up to 200,000 members, is a major reason the platform has been criticized. These unmoderated public channels have also become fertile ground for the distribution of misinformation and illegal content, such as revenge and child pornography. But unlike WhatsApp, Telegram has refused to reduce that limit.

Telegram is free for iOS, iPadOS, Android, macOS, Windows, Linux, and on the web.

Dust

Less popular than Signal or Telegram, Dust is a good option if you want to keep your content as secure as you can. Beyond E2E encryption, the app has a privacy-focused functionality that lets users hide their tracks online, and a monitoring system that will instantly alert you if any of your passwords are compromised as part of a data leak.

By default, messages (or “dusts”) disappear from the app’s servers right after you send them, and chat histories are automatically erased from your phone every 24 hours. On top of that, you (or your contacts) can delete messages on both ends of the conversation with just one tap, and you can sign up by using only your phone number.

The bad news is that the platform doesn’t currently support video calls or voice messages—only texting, file sharing, and voice calling—which may be a deal-breaker if you want a more comprehensive service.

Dust is free for iOS and Android.

There are a lot of secure messaging apps to choose from.
Protect your data by choosing secure messaging apps. Chris Yang / Unsplash

Threema

This app is open-source, E2E encrypted, and—just like Dust and Signal—deletes messages from its servers right after they’re delivered. Threema doesn’t require a phone number or email to sign up, instead verifying each user with a Threema ID, an 8-digit number that allows them to be completely anonymous.

Threema supports texting, voice and video calls, but its major drawback is that you have to pay for it. The company says this allows its developers to sustain the platform without ads or data-harvesting, and it might also explain why it only had 11 million users worldwide as of October 2022. You can use it on the web, Windows, and macOS, but there are restrictions and you need to have the mobile app on your phone or tablet.

Threema is $5 for iOS, iPadOS, and Android.

Viber

Like many of the other apps on this list, Viber will protect your content (texts, voice calls, and video chats) with default E2E encryption, whether you’re engaging in one-on-one conversations or group interactions. Chatbots and communities are the exceptions to this rule.

If you choose this app, you’ll have to make sure you have version 6.0 or later, as they’re the only ones with E2E-encrypted messaging. Unfortunately, you’ll also have to worry about what version other people have, too: if you’re chatting with someone using an older version of Viber, you can kiss E2E encryption bye-bye. If you’re unsure if a chat is E2E encrypted, you can check by going to the chat info screen and looking for a lock icon next to Encrypted chat. 

[Related: The best apps for sending self-destructing messages]

Just like Telegram, Viber also has public channels called Communities, and these messages are only SSL encrypted. This protects data in transit, but once it’s on the app’s servers, it’s readable by Viber or any other member of the community, allowing new members to access all backlogs.

Viber’s privacy features include the ability to set self-destructing timers for messages, edit and delete messages on all devices with a tap, and either get notifications if a user takes a screenshot of a disappearing message (iOS) or blocks the screenshot altogether (Android). You can also create Hidden chats and access them with a PIN whenever you want, 

Viber is free for iOS, iPadOS, Android, Huawei’s App Gallery, macOS, Windows, and Linux.

iMessage

If you’re an Apple user, you’re in luck, as you have access to the company’s built-in E2E encrypted messaging platform. Now, the catch is that iMessage only works with this security standard when you’re chatting with other Apple users—if one of your friends uses an Android device, privacy pretty much goes out the window.

Because iMessage doesn’t play nice with other messaging apps, it immediately switches to the not-so-good-ol’ SMS message whenever it cannot use Apple’s protocol, turning chat bubbles from blue to green. This type of message is reliable, as it doesn’t require your device to have lots of bars to work, but it’s neither secure nor private—SMS messages can be traced, intercepted, and stored by your service provider, who can gladly hand them over to authorities, if asked politely.

This is also an issue for interactions between Apple users, though. By default, iMessage switches gears also when connectivity is low. The problem is that you won’t actually know if this has happened, as individual bubbles in your chats won’t change color to show how they were delivered.

The good news is that you can disable this feature—just go to the Messages settings menu and turn off the toggle switch next to Send as SMS.

iMessage is built into Apple devices.

Updated February 4, 2021 to more accurately reflect that Telegram’s user base as of January 2021 was 500 million users worldwide.

This story has been updated. It was originally published on January 18, 2021.

 

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