Source: Microsoft

At its Microsoft 365 Developer Day, Microsoft today debuted a number of new tools for developers who want to adapt their application to Windows 10X, the company’s version of Windows for dual-screen devices.

The highlight here is the launch of a Windows 10X emulator, which allows developers to preview what their applications will look like on a dual-screen device. As of now, there’s no Windows 10X hardware on the market, after all. Microsoft’s own Surface Neo and a number of devices from various other manufacturers are slated to hit the market before the holidays, but by that time, Microsoft obviously wants developers to be ready for this new user experience.

Microsoft notes that all current Windows applications will work on dual-screen devices by default — but in order to really make use of this new form factor, developers will have to adapt their applications for it. Currently, Microsoft is looking at three patterns for these applications: expansive workspaces that essentially expand an app across two screens, focused screens that put the app onto one screen and its tools on another, and connected apps for used two apps side-by-side for easier multitasking.

With the new emulator and Preview SDK, developers will be able to see what works best for them.

The company also today proposed new JavaScript APIs and a CSS media query for helping developers who build their apps using HTML, CSS and JavaScript as PWA or WebViews to make use of the two screens of these new devices. The company says it’s working with the W3C to make these a standard. “The goal is to enable you to build interoperable dual-screen experiences across browsers and operating systems,” Microsoft says.

Xamarin, Microsoft’s cross-platform development platform, is also getting dual-screen support in Xamarin.Forms, its UI toolkit, and the company is also making React Native dual-screen modules available to developers.

The idea here is clearly to give developers the tools to figure out how to make use of these devices. While the company clearly has some ideas for what it believes the best user experience will look like, it also wants to see what developers come up with. It’s still early days for dual-screen Windows devices, after all, and there is still time for Microsoft to learn from the ecosystem and adapt accordingly.

The company tells me that it still expects to deliver the new Surface hardware and Windows 10X before the holiday season.

Microsoft launches new dev tools for building Windows 10X dual-screen experiences