Must-have mobile apps to encrypt your texts and calls

Signal is a free app for Android and iOS mobile devices. A firm favourite for the security-conscious, the application encompasses encryption for both messaging and calls which is continually audited and checked for security issues. The strength of this app is the user friendliness of the software, which means you do not need advanced technical knowledge to take advantage of encryption.

Price: Free

Via: Google Play | Apple App Store

Silent Phone is one of several encrypted communication services offered by Silent Circle, the developer behind the Blackphone security-focused smartphone range.

Silent Phone is a subscription-based service which harnesses end-to-end encryption with the keys held by the subscriber rather than the company, and so no government eyes can snoop on your calls. The service also offers secure conference calls, messaging and file transfers.

Via: Silent Circle

In April this year, WhatsApp announced the introduction of end-to-end encryption for users worldwide. While this has upset some governments in countries including Brazil, this encryption will help keep your Android and iOS messages safe from spying eyes.

Via: WhatsApp

Viber recently announced the introduction of end-to-end encryption on the chat platform, and a handy feature is called "Hidden Chats," which hide 1-on-1 and group chat sessions on a device which can only be unlocked by a secret PIN number.

Via: Viber

ChatSecure, available for Android and iOS, is a highly-rated open-source encrypted messaging option which supports OTR encryption over XMPP. While this option is best for Android users -- as Apple does not permit an 'always on' setting on iOS for the app -- the app is also flexible and can be used with other XMPP-based software.

Via: ChatSecure

While the numbers of BlackBerry users have dwindled in recent years with the rise of iOS and Android, BlackBerry Messenger (BBM), which can also be used on other operating systems. Messages sent through the service are encrypted and pass through both a firewall and BlackBerry servers before being passed on. Decryption keys on the recipient's device are the only way messages can be unpacked.

Via: BlackBerry

Available for Android and iOS, Wickr is an app for secure messaging. The strength in the app lies in the self-destruct feature for messages, allowing you to set a time and date for your messages to expire and become automatically deleted. This can help shield your communication from third parties, and every message sent is also passed via end-to-end encryption.

Via: Wickr

It isn't common for default mobile apps to also offer decent encryption and protection, but Apple's iMessage does. The app supports end-to-end encryption -- which means that even the company itself cannot give law enforcement access to conversations unless message backups are stored in an unencrypted fashion to the iCloud.

Via: Apple

In a move praised by many, the social media giant recently announced plans to roll out end-to-end encryption for conversations taking place on Facebook. While the security enhancement isn't yet worldwide, if you already have the option, you need to opt-in through the settings tab to keep your conversations safe.

Via: ZDNet