You have to open the mobile phone app and use the scanner available in the Settings > Linked devices menu to scan the QR code displayed within the desktop app's start screen. To install Signal on your desktop, you will be asked to pair it with the application on your iOS or Android smartphone in order to have your messages synced at all times. Simple to install instant messenger with end-to-end encryption Moreover, Signal helps you use an end-to-end encrypted connection to chat with your contacts, with the keys (also known as safety numbers) used to encrypt it being stored on the end devices and easily verifiable to instantly check and verify the identity of the person on the other end.

Signal is an open-source and secure instant messaging application which enables you to securely communicate with your friends, colleagues, and family using text, images, audio and video content using macOS, iOS, Windows, Linux, and Android devices.