Signal's latest beta version allows users to link an Android phone or tablet to an existing account as a secondary device, enabling synchronized chat history across multiple devices without needing a separate number. Users can link devices by downloading the Signal app, initiating the welcome process, and scanning a QR code displayed on the new device with their primary device. Additionally, Signal has introduced a split-screen interface for tablets, featuring a chat list and an active conversation panel optimized for landscape mode, with customization options available.