Security & Privacy

More and more people communicate via messaging apps, as phone calls are seen as old-fashioned, and email can be too complicated. Messaging has the advantage of being more conversational than email, and more immediate.

Unlike in the early days of messaging, such as SMS and AIM, many of today’s messaging apps are secure, with end-to-end encryption protecting your conversations. Messaging apps can be a great way to send sensitive information to others, even to send passwords or other user credentials.

Here are five secure messaging apps you can use, on Mac, iPhone, and iPad, as well as on other platforms.

iMessage

Cost: Free

Compatibility: macOS, iOS, iPadOS, watchOS

Offered by Apple, iMessage has been available on iOS since 2011, macOS since 2012, and watchOS since 2015. It is by far the most convenient way to securely send messages for users of Apple devices. Using end-to-end encryption by default, it is very secure. Only you and the person you’re messaging can get to the contents of an iMessage conversation. More on iMessage security can be found in this Apple Platform Security document.

For Apple device users, setting up and using iMessage is very easy. Sign into your device with your Apple ID, or create a new one, and you’re good to go. There aren’t many settings you can adjust. You can choose which phone numbers and email addresses people can use to contact you. And you can enable or disable read receipts. On iOS, you can also set a low quality image mode, and you can enable text message forwarding, so SMS messages sent to your iPhone can be forwarded to your other devices. There are a few other settings for iOS and iPadOS, and if you have an Apple Watch, you can choose whether dictated messages are sent as text or audio, and set some default replies that you can tap on the screen of your watch.

Of all the apps mentioned in this article, Messages is the only one that has an Apple Watch app. This could benefit you if your child has an Apple Watch SE but doesn’t have their own iPhone.

There are a couple of important caveats that may convince you to use an alternative platform, however.

While the platform is called iMessage, the Apple app is called Messages. It’s important to understand that you can send both iMessage (secure) and SMS (insecure) via the Messages app. You’ll know you’re about to send an iMessage if the round “send” arrow button is blue, and you’ll notice that your messages will have a “blue bubble” as well. (If your “send” arrow button is green or your outgoing messages appear in a “green bubble,” this means your recipient is not using iMessage. For now, that means your texts will be sent insecurely via the antiquated SMS system. This most likely means that the recipient has an Android or other non-Apple phone, and cannot use iMessage.) By late 2024, Apple plans to add support for RCS to its Messages app in iOS 18, which will allow secure messaging with some Android users; the chat bubbles will still be green, however. (We discussed Apple’s plans to add RCS in episode 319 of the Intego Mac Podcast.)

You can choose whether or not to enable Messages in iCloud, so your iMessages can be recovered in case you lose all your trusted devices. (To find this setting, search your iOS Settings app for the word “Backup,” tap on it, and then look for “Messages” in the “Apps Using iCloud” list.) Note that if this setting is enabled, your decryption key is stored on Apple servers, which is less secure. You have no way of knowing whether the person you’re messaging has this setting enabled or not. If that concerns you, then you may wish to choose another app below for more secure communications.

Signal

Cost: Free

Compatibility: macOS, iOS, iPadOS, Android, Windows, Linux

Signal is most well known for its endorsement by Edward Snowden, who says, “I use Signal every day.” Signal uses end-to-end encryption to keep your communications private and secure, including private messaging and private calling, and the Signal protocol is becoming a standard in messaging services (WhatsApp, notably, has adopted the Signal protocol).

The setup and use of Signal is very straightforward. Even if you only end up using the iOS version of Signal, its security alone might make it worth it for you. You can sync Signal messages across devices, on an iPhone, iPad, or Mac, as well as Windows devices. A fairly large number of people use Signal, although it isn’t as popular as WhatsApp or Telegram.

WhatsApp

Cost: Free

Compatibility: macOS, iOS, Android, Windows, KaiOS, Web

WhatsApp, which was acquired by Facebook in 2014, started offering end-to-end encryption in mid-2016 and uses the Signal protocol. In spite of its ownership by Facebook—a company for which privacy is not a key feature—WhatsApp can be considered a secure messaging app. Your communications are encrypted, so only you and the recipient can see them.

While WhatsApp is not as widely used in the United States or Europe, it is the predominant mobile platform for communication, commerce, and more in India, where it may reach 500 million users soon. It’s also popular in many other countries. Based on our limited testing, WhatsApp may be the second most commonly used messaging app on this list, behind iMessage, in the U.S.

WhatsApp introduced a new privacy policy in early 2021, causing some consternation. Reportedly, users who didn’t accept the changes would gradually lose features until the app stopped working. While WhatsApp conversations are still encrypted, “WhatsApp will be able to share user account information like your phone number, logs of how long and how often you use WhatsApp, device identifiers, IP addresses, and other details about your device with Facebook.”

While WhatsApp is available for macOS, the Mac version is not really a stand-alone app. Your phone must be on the same Wi-Fi network, and the macOS version will not work if your phone is not available.

WhatsApp is supported on iPhone, but isn’t supported on iPad or iPod touch (however, WhatsApp offers a Web app that can be used in a browser).

Telegram Messenger

Cost: Free

Compatibility:  macOS, iOS, iPadOS, watchOS, Android, Windows, Linux, Web

Telegram is very easy to use, and it’s available on more platforms than any other app on this list. It offers plenty of settings to set it up how you like it. Two-step verification, password protection for the client, and various settings to customize the look and feel of the chat are a few examples why Telegram can be a decent messaging app option.

However, it’s very important to note that chat encryption is not enabled by default. This is concerning, because it means Telegram users must be diligent about initiating “Secret Chats” with their friends. The encryption that is used, once enabled, is based on the MTProto 2.0 mobile protocol. Unfortunately, Telegram does not encrypt group chats.

Telegram has been broadly criticized for a number of reasons. Thus, although Telegram is well known and available on many platforms, it may be worth looking into other alternatives before deciding whether to use it.

Threema

Cost: $5.99 one-time app purchase (iOS/iPadOS) or $6.99 (Android)

Compatibility: macOS (beta), iOS, iPadOS, Android, Windows (beta), Linux (beta), Web

Threema is an anonymous encrypted messaging platform. Threema does not link your account to your phone’s SIM card, but to a Threema ID which is generated when you sign up. You can use Threema with an iPhone, iPad, or a limited web version.

One unique advantage of Threema compared to the others on this list is that you can create an account anonymously, and without having to provide a mobile phone number. This gives Threema some additional niche use cases; for example, a parent can use it to securely message with a child who only has a Wi-Fi capable device like an iPod touch, iPad, or Android tablet. (Threema doesn’t have an Apple Watch app, however; you’ll need to use iMessage to communicate with someone who only has an Apple Watch.)

But there’s another way in which Threema is unlike the other apps listed above: you have to pay for it. A one-time purchase of the Threema app gives you access to the service. Because of this, fewer people use Threema. But if you have a small group that wants secure, anonymous messaging that doesn’t require a phone number, Threema might be for you. The company also offers plans for businesses and organizations.

Other messaging apps

There are a handful of other messaging services marketed as being secure. Many such apps have known issues or potential concerns, such as the reliability of their encryption, how they handle user data, and who owns them.

An independently run site called Secure Messaging Apps Comparison includes a chart featuring its author’s extensive feature comparisons.

Of the apps we’ve listed above, the site’s author, Mark Williams, only recommends Signal and Threema. Williams recommends two others as well: Session and Wire. In our limited testing, it seems that far fewer people use these platforms than most of the other messaging apps listed above.

If you and your friends, loved ones, or associates haven’t yet decided which secure messaging platform to use, you may find it helpful to dig into the extensive details that the site has compiled about each service.

Some other notable messaging apps that are listed on Williams’ chart, but not recommended by Williams, include:

• Google Messages
• Facebook Messenger
  • Note that Facebook Messenger has begun to include end-to-end encryption for some chats, as we discussed in episode 322 of the Intego Mac Podcast.
• Element
• Microsoft Skype (one of the worst, in Williams’ view)
• Viber
• Amazon Wickr Me (discontinued; Wickr is now enterprise-only)
• SimpleX (a newer contender; Williams hasn’t decided whether to recommend it yet, but it looks promising)
• X, formerly known as Twitter
  • Note that encrypted messaging is only available to verified users (i.e. paying users, or accounts with at least 2,500 verified followers, or accounts that are affiliates of a verified organization).

Additional tips for secure communications

Regardless of the messaging or communication tool you use, you may want to use a VPN such as Intego Privacy Protection to add an extra layer of protection, especially if you don’t fully trust the network or Internet service provider to which you’re connected. Although the network operator may be able to tell that you’re using a VPN, the operator won’t be able to see that you’re using an encrypted chat app (or any other apps or sites). This also adds the benefit of hiding your IP address when making secure calls.

How to avoid exposing your IP or location in FaceTime, WhatsApp, Telegram, Signal, X, and other apps

Messaging and email offer different advantages and disadvantages. You may also want to use secure email, and you can read our examination of a few free secure email services that protect your data and privacy.

Three Free Secure Email Providers That Protect Your Data and Privacy

In addition to using a secure messaging app, you should use an anti-virus and two-way firewall solution on your Mac to make sure malware and key loggers can’t monitor your chats.

Furthermore, in case your Mac ever gets lost or stolen, use FileVault disk encryption and a strong login password to prevent access to your chat apps and other data. On an iPhone or iPad, consider using a complex password alongside Face ID or Touch ID; see our comparison of Face ID, Touch ID, and passcode security. (Apple’s iOS uses full storage encryption by default.)

Using messaging, or any form of online communications, is not as worry-free as it once was. However, given the improvements in security, there is much to be said for these apps. By using secure, encrypted messaging apps, you can carry on communicating with friends, family, and colleagues, knowing that your conversations remain private.

How can I learn more?

Each week on the Intego Mac Podcast, Intego’s Mac security experts discuss the latest Apple news, security and privacy stories, and offer practical advice on getting the most out of your Apple devices. Be sure to follow the podcast to make sure you don’t miss any episodes.

You can also subscribe to our e-mail newsletter and keep an eye here on The Mac Security Blog for the latest Apple security and privacy news. And don’t forget to follow Intego on your favorite social media channels:      

About Jay Vrijenhoek