You might have heard about the operating system, dubbed Andromeda OS, that Microsoft was working on in the past. It was reported that Microsoft was building Andromeda OS for a dual-screen form factor, and that it would eventually have made it to the Surface Duo.
However, it didn"t happen, and the Surface Duo launched with Android. Microsoft canceled plans for Andromeda OS back in 2018, and since then, the unfinished OS remained out of the limelight until recently, when a leaked build of Andromeda OS appeared online.
A developer named Gustave Monce spent time and energy porting the leaked build to the original Surface Duo. You can download the leaked build as an FFU file containing "Windows 8828080 for Surface Duo" and find the flashing instructions on the developer"s GitHub repo. The Andromeda OS port is not available on the Surface Duo 2 due to a lack of driver support, according to the developer.
— Gustave Monce 🦉 (@gus33000) December 24, 2025
The Andromeda OS port gives a first real-world look at what Microsoft was trying to bake for its dual-screen device. The build is unfinished and dates from after the project was scrapped by the Redmond giant, according to Windows Central, which was the earliest to report it.
It"s recommended to read everything carefully if you want to try it out. The installation process will wipe your Android data, as per the repo. The build is buggy, and Gustave is working to fix some of its issues. Still, it brings back the charm of the old Start Menu and Live Tiles, which were once a USP for Windows.
Gustave said that the Surface Duo will have Android and Windows after installation, with both operating systems sharing the internal storage. While you"ll be able to boot into Android normally, you will need a PC to boot Windows. The instructions include the steps to create a dual-boot image to get around this issue.