Signal Encrypted Chat App Adds Video Calls, iOS Users Beware

At the height of the great Snowden whistleblowing phase of history, highly secure and encrypted messaging services became en vogue. While some of that has died down, a notable few like Signal remain. Developed by Open Whisper Systems, which also developers the Signal protocol now used by Whatsapp for encryption, the Signal app started out as a simple, text-based chat app. Now it is on the cusp of its next evolution, adding that oh so popular video chatting capability, though still in beta format.

Signal started out as a chat app but soon graduated to making voice calls. Following the trend of many messaging services these days, Signal has also added making video calls. Its difference, of course, is that Signal promises an extra measure of security and privacy that other chat apps, driven by profits, simply can't deliver.

The development of video calling capabilities has more significance than just the addition of the feature itself. It further unities Signal's disparate channels and protocols. Although it now comes as a single app, under the hood Signal still uses different technologies and protocols for its text and voice systems. The addition of video calling allowed Open Whisper Systems to migrate some parts to its own Signal Protocol and drop other unused or slightly less secure systems as well.

The new beta video calling feature has one rather ironic caveat that affects only iOS 10 users. The feature takes advantage of the OS' CallKit API, which would allow Signal users to answer a call with one tap, even from the lock screen. This, however, comes at a price. CallKit sees VoIP calls like these as regular calls and therefore logs them in the Recent Calls list, which includes information on who called and for how long. This could potentially be synced to iCloud, depending on the user's settings, which sort of defeats the purpose of a completely private call.

The good news is that the feature is completely optional and can be disabled from within Signal. CallKit integration only happens if both parties have it enabled, so disabling it on your end effectively makes sure your calls never get recorded no matter what. Open Whisper Systems is still deciding whether to disable that feature by default in the final version.

SOURCE: Open Whisper Systems