Microsoft and its partners recently started shipping the first wave of Windows 10 devices powered by Qualcomm’s Snapdragon 835 processors. These devices, powered by Windows 10 S, are capable of running ARM and x86 UWP applications as well as x86, ARM, and ARM64 classic desktop applications, thanks to Microsoft’s Windows on Windows compatibility layer.
Redmond is now working on officially supporting 64-bit (ARM64) apps on its Windows on ARM platform. Windows General Manager Erin Chapple reportedly told Engadget that the company is going to be releasing a new “SDK for ARM64 apps” that will allow developers to build 64-bit applications for Windows 10 devices powered by ARM processors, or recompile their existing apps for 64-bit. (This is not to be confused with 64-bit AMD64 support, which is not happening any time soon, if ever.)
The company plans to release the new SDK this May at its Build 2018 developer conference.
UPDATE: Here’s a Microsoft statement addressing the confusion around this topic.
“To clarify, Microsoft is planning to release a preview of the Windows 10 ARM64 SDK for Store and desktop apps, allowing developers to recompile their Win32 desktop apps to ARM64 so they can run natively without emulation,” the Microsoft representative told me. “With the SDK, x64 apps and x86 apps will also be able to recompile to ARM64 and run natively. We will be sharing more details on the ARM64 SDK Preview at Build.”