Linking devices in Signal means that you can use a single Signal account on multiple devices at the same time, such as your phone, computer, PC, laptop, or iPad. It is not possible to link a phone to another phone.
Once a device is linked, your messages and chats are synced across all connected devices, so you can continue chats seamlessly.
Your phone does not need to stay online for a linked device to work. However, if you have not used Signal on your primary device for a long time, you may receive a notification asking you to open it to keep your account active.
A linked device will automatically unlink after 45 days of inactivity.
You can link up to five devices to one phone, and you can choose to synchronize your chat history when you first set up a linked device. Your entire message history and the last 45 days of media can be synchronized from your mobile phone. If you use the paid version of Signal Secure Backups, all media will be included.
You can manage or view your linked devices via Signal Settings > Linked devices.
