iPhone 7
The fast adoption rate may have also been caused by users activating their newly-bought iPhone 7 and iPhone 7 Plus. Sean Gallup/Getty Images

This year saw an increase in the level of security for some major messaging services, including Facebook Messenger and WhatsApp.

With the incoming administration headed by president-elect Donald Trump, there was even more interest in encrypted messaging. End-to-end encryption app Signal saw a 400% spike in sign ups the week after the US presidential election in November.

Here are the top five free encryption apps:

Signal

Open Whisper System’s Signal uses an advanced end-to-end encryption protocol to send messages, group messages, media and voice calls. The app also lets you self-destruct messages after a certain timeframe. Signal is the only private messenger that uses open source peer-reviewed cryptographic protocols to keep your conversations safe, the app says. The app uses your current phone number and address book, which means there is no need for separate logins, usernames, passwords, or PINs.

The app is free of charge for iOS and Android devices, and also has a Chrome browser plugin that lets you use Signal from your desktop.

Wickr Me

Wicker Me is a free end-to-end encrypted messaging app for Android and iOS devices. It uses industry-standard AES256 encryption to secure data. Wickr Me lets users send private, self-destructing text messages, media and voice messages to other contacts with the app.

Wickr Me takes your privacy seriously too. It removes all metadata, including records, geotags and identifying information from your messages and media. The app also does not collect or store any of your personal data to sell. (Here’s a video on how it works.)

WhatsApp

Popular chatting app WhatsApp added end-to-end encryption this year. WhatsApp partnered with Open Whisper Systems, in 2014 to make it happen. The app has a security-verification code that users can compare with a contact to make sure their conversation is secure. WhatsApp is available for Android and iOS devices.

Viper

Viper announced its revamped security on its app when it launched its 6.0 update. The app now has end-to-end encryption for calls, messages, group messages, media and secondary devices. Users’ encryption keys are stored for consumers themselves, which mean Viper doesn’t have access to them either. Viber's protocol uses the same concepts used in Open Whisper Systems Signal app, however, Viber's implementation was developed from scratch and does not share Signal's source code, it said in its Viber Encryption Overview. The app is free for iPhones and Androids.

Chat Secure

Chat Secure, created by the Guardian Project, is a free and open source messaging app for Android and iOS phones. The app features off-the-record encryption over XMPP, which offer complete and secure private messaging. Users can connect to their existing accounts on Facebook or Google, create new accounts on public XMPP servers, or connect to their own server for extra security, the Guardian Project says.