Hardware The Surface Duo is a
folio-styled device, with two 5.6-inch
OLED displays with a
4:3 aspect ratio. When unfolded, they form an 8.1-inch surface with a 3:2 aspect ratio and total resolution of 2700×1800. The 360-degree hinge allows the device to be used in several "postures", including being fully unfolded as a flat surface, a landscape mode where the
virtual keyboard occupies the entirety of the bottom screen, and the other screen folded backwards for single-screen use. It is compatible with
Surface Pen styluses. It uses a
Qualcomm Snapdragon 855 system-on-chip with 6 GB of RAM. Microsoft stated that it worked with Qualcomm to optimize the device for multitasking. When unveiling the Surface Duo, Microsoft avoided referring to the device as being a "phone", with chief product officer
Panos Panay primarily referring to it as a "Surface device"
Software The Surface Duo ships with
Android 10 and
Google Mobile Services, and is pre-loaded with both Google and Microsoft-developed apps. The two displays are designed to act like a
multi-monitor configuration on a PC; individual apps can be displayed across the displays, an app on one display can open external links on the other, and supported apps can display different views on each display. Microsoft stated that it would contribute the associated
APIs for these features to the upstream Android Open Source Project (AOSP), so that this functionality could be leveraged by other dual-screen and
foldable smartphones. The update was released in February 2022.
Android 12 L was released in October 2022, seven months after its release. Microsoft stated that the update would include visual elements of
Windows 11 and
Fluent Design System. The ARM version of Windows 11 was adapted to function on Surface Duo by a third-party developer. On September 10, 2023, Microsoft stopped releasing all updates for the device, including security patches. == Reception ==