The topic of smartphone security and secure communication is front and centre these days, thanks to the battle between Apple and the FBI over opening up an iPhone used by one of the San Bernardino, California, mass shooters.
The case has raised questions about what means people might have to protect their mobile data, shining the spotlight on the many apps that promise secure emailing, messaging and more.
Signal, one of the best known private messaging apps, is free on iOS and Android. Its makers promote it with the slogan “privacy is possible,” and it uses end-to-end encryption, ensuring that only the recipient of the communications can read them. Its encryption and privacy protections are highly rated by the Electronic Frontier Foundation, a digital rights group.
Signal’s users can send secure messages and make Internet voice calls with their existing phone number, and there’s no need to set up an account. The app is straightforward to use, with large icons and controls and large, easy-to-read text.
To talk, both parties must have Signal installed. And for an extra level of protection, which takes a little getting used to, both parties are shown a random pair of words that allows them to double-check that the other user is the right person. The technique brings spy movies to mind, but it’s a strong reminder that you are taking part in a secure call.
Threema delivers a similar service with a few more features. It also has end-to-end encryption, which is applied to all communication including text messages and files and images sent via the service. There’s no voice call capability, but users can send voice messages. Both sender and recipient must have Threema installed.
Additionally, Threema allows users to hold group chats and to pose a question as a poll to group members. There’s no need to open an account to use the app, because each user is assigned a random ID that isn’t necessarily connected to an email address or phone number. There’s more to learn within Threema in terms of controls and menus, but they are relatively easy to master. The app is available on iOS, Android and Windows Phone, and costs $3 ($2 on Windows).
Wickr Me, which is free on iOS and Android, is something of a celebrity in this class of apps because it was featured in an Iggy Azalea music video. It also has fun touches, including the ability to add stickers, graffiti and filters to photos. But at its heart, Wickr Me is a secure messaging app. Users can set an expiration time for messages, and it offers encryption for voice, text and video messages. A “shredder” function promises to securely erase all deleted messages and media from your device. Wickr Me also allows for anonymous use, so not even Wickr’s makers know who its users are.
For a more traditional secure email app, check out ProtonMail. Free on iOS and Android, ProtonMail looks like a typical email app—except that all emails sent and received through it are encrypted. When you sign up for a free account, it’s emphasised that if you forget your passwords, there’s no way you can retrieve your emails. The app’s single purpose of delivering secure emails means ProtonMail is not the fanciest app in the world, but it’s easy to use. The app works best when the sender and receiver both have ProtonMail, but there is a way to send encrypted messages from inside the app to more standard email addresses.
All of these apps help augment the encryption that may already be built into your device. (It’s worth checking through your phone’s settings to familiarise yourself with its privacy and security features.)Some secure messaging apps may be misused, which is why many of them ask upon sign-up that you won’t use them for illegal purposes. And remember—there’s no such thing as perfect security, particularly if you lose your phone.