Recent images reveal that the Surface Duo was initially conceived as a Windows Phone codenamed Andromeda, featuring a custom-built operating system designed for its dual-screen form factor. The project was shelved in 2018 due to challenges faced during development. Prototypes from 2017 and 2018 show that Andromeda included features such as a back camera system, integrated wireless charging for the Surface Slim Pen, and a premium metal frame, which were not present in the final Surface Duo. Andromeda also had smaller hinges, which were later enlarged in the Surface Duo for added stiffness. The operating system for Andromeda was based on Windows Core OS, featuring a universal shell for dual-screen use, a home screen designed for note-taking, and a lock screen that functioned as an inking canvas.