Signal App: Secure Screen Sharing
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Signal is a very secure messenger app. I love Signal to call my friends and colleagues. For a long time, I missed Group-Calls, but the December 2020 release of Signal App introduced “Group calls”. Finally!
Still, I missed a feature to share my PC Screen with other users, e.g. for work or Home-Schooling. So I’ve checked the Signal Desktop App. Unfortunatly the Desktop App has no “screen-sharing” button :( — at a first glance there is no native support for THE feature I want. Then I discovered the option to chose a different Camera Device in the call settings. Bingo! The camera devices listed my OBS virtual camera. When I start OBS Virtual Capture, everybody can see my screen in the viedeo-call!
You may ask why is Screen-Sharing via Signal Desktop such a cool feature? Well, there is more than a single answer to it:
- No privacy concerns. Signal implements secure end-to-end encryption protocol and you don’t need to be afraid of unwanted data sharing policies — unlike WhatsApp, Facebook, Google or any other commercial data miners
- No commercial licenses, unlike WebEx, GoToMeeting, MS Teams …
- Perfect for regular meetings with a group of people — like a class room or team at work
- OBS and Signal are transparent open-source projects
So let me show step-by-step, how screen sharing works with the Signal Desktop App:
- Create a Signal Group in the Signal App
- Invite Group Members
On your PC:
- Install OBS Studio
- Install OBS virtual camera
- Install Signal Desktop App
- Link your Signal Desktop App with your phone by scanning the displayed QR code with your phone
Now, it is time to make the first secure group-call for a presentation or work meeting:
- Start OBS Studio and activate the virtual camera capture
- Call your Signal Group
- Switch Camera setting in Signal Desktop App to “OBS virtual camera”
- All users should see your Desktop and everything is end-to-end encrypted
Signal is a great tool for secure personal communication. With my little setup, you can turn Signal Desktop into a productive tool for work or school. Enjoy!
