Popular paid messaging app Threema has announced the availability of video calls with end-to-end encryption. The feature was being developed since last year and was in beta testing since April this year.
Along with ‘crystal clear’ audio and ‘brilliant’ image quality, Threema promises the same privacy protection to video calls it offers for chats and audio calls. During video calls, the call data, meta data as well as signalling is fully end-to-end encrypted. The company says that all encrypted video calls are established between users without having to pass Threema servers (peer-to-peer). Threema makes use of WebRTC streaming protocol and calls are encrypted on user’s device using locally stored encryption key.
When a user is having a call with an unverified user, packets are relayed through Threema’s TURN servers. According to Threema’s cryptography whitepaper, relaying provides privacy protection by hiding a user’s public IP from untrusted caller. This practice, however, exposes some metadata to the TURN server while also increasing latency and reducing call quality.
To make an encrypted video call, users have to simply start a regular call and turn on the camera. To completely disable the video call feature, one can go to Settings > Threema calls and turn off ‘Allow Video Calls’ option.
While there are many ‘free’ messaging apps that offer end-to-end encrypted chats and calls, Threema – a paid app – remains popular among privacy-concious users. It does not require a phone number or any other identifier to create an account. To start using the app, users generate a Threema ID and can optionally add a phone number or an email address to their ID.
With E2E encrypted video calls, Threema has given one more reason for users to switch to a paid, privacy-first messaging app.