Instant messaging (IM) apps are convenient software that lets people message anyone, anytime, anywhere. These apps also give people various options to express themselves in ways they normally couldn't when done through emails.

Additionally, instant messaging apps are also handy due to how easy they are to use. Adding people is as easy as permitting an app to access a user's phone contacts or typing their contact number, username, or email address. Sending photos, videos, and audio recordings through instant messaging apps is easier compared to attaching them in emails.

In many ways, emails are now mostly used for formal messages, while IM apps are for impromptu and less formal methods of communication.

However, not all of these IM apps are safe. Not all of them come with end-to-end encryption (E2E), a level of encryption that prevents third parties (like hackers) from accessing data while it's transferred from one device to another, per Tech Target.

Here are some instant messaging apps that come with such encryption.

Signal Private Messenger

The Signal instant messaging app is one of the free instant messengers that use end-to-end encryption to protect people's conversations. However, unlike other secure messaging apps, Signal encrypts all kinds of conversations on its platform, per Signal's support center. This protection means that the app encrypts chats, video calls, and video calls, giving users the privacy and security they need to discuss topics usually reserved in person.

The app is operated by the non-profit organization, Signal Foundation and is endorsed by Edward Snowden. According to Wired, messages in Signal aren't stored in any cloud server and are stored in a user's phone instead.

The app is available for iOS and Android devices as well as PCs.

Telegram Messenger

Telegram, another free secure messaging app, uses E2E encryption and is based in Dubai. Like Signal, it also uses encrypts voice calls and video calls, protecting them from third-party access. The app's FAQ page mentioned its encryption is based on the MTProtoco protocol to make security compatible with high-speed delivery and reliability on week connections, per its FAQ page.

The app also features secret chats that prevent anyone, even Telegram, from reading messages sent using this feature.

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Additionally, several court orders from different jurisdictions are required to have Telegram divulge a user's data to anyone. However, E2E encryption isn't enabled by default as users have to manually enable it through its "Secret Chat" feature.

Telegram is available on iOS and Android devices and PCs.

Viber

Viber is one of the free secure messaging apps that is available on all platforms while having E2E encryption. The app was based in Israel before it was bought by Japanese e-commerce company Rakuten, per Tom's Guide.

The app features a color-coded lock icon to help users identify whether a conversation is protected. A gray lock is for encrypted communications while green is for secure communications with a trusted contact. A red lock is a sign that there is a problem with the authentication key. Aside from that Viber has self-destructing secret chats, which can also be used in group chats and its desktop counterpart. Like Signal and Telegram, Viber also uses E2E encryption for video calls and video calls, per the app's website.

The only problem with Viber is that its source code isn't open-source, meaning that you'll have to trust Viber with security, per AVG.

Threema

Unlike the first three apps on this list, Threema comes with a $3.99 price tag. Despite that fact, it does function well as a secure instant messaging app.

The company that developed and operates the app, Threema GmbH, is based in Switzerland, per the app's official website.

Threema doesn't require personal information and has minimal data collection. It even has a Hidden Chat feature that can only be accessed with a user-made PIN.

Additionally, one of the app's nifty features is the ability to give other Threema users a scannable QR code for them to scan to avoid revealing names.

The only downside, according to Tom's Guide, is that the app hasn't caught on with the English-speaking world despite its 4.5 million users, per Stream. This fact may be due to the app being popular in Germany.

Threema is available on iOS and Android devices.

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