Microsoft wants those developers to make apps for the OS that will work with everything from small smartphone screens to the Xbox One console to large touchscreen devices like the upcoming Surface Hub. In a blog post today, Microsoft's Kevin Gallo stated:
"As we built the universal app platform, we set out to ensure that all Windows developers would equally benefit from this one core. The platform enables a new class of Windows universal apps – apps that are truly written once, with one set of business logic and one UI. Apps that are delivered to one Store within one package. Apps that are able to reach every Windows 10 device the developer wants to reach. Apps that feel consistent and familiar to the customer on all devices, while also contextually appropriate to each device's input model and screen size. The new universal app platform completes our developer platform convergence by providing you with the ability to finally create one app that can run on mobile, desktop, console, holographic, and even IoT devices."
As you might expect, interacting with an app on a small smartphone touchscreen is different than using the same app on a larger tablet or the Xbox One. Gallo wrote:
"Windows 10 will determine, at runtime, how the customer is interacting with your app and render the appropriate user experience (e.g. on a laptop with a touch-screen, an app fly-out control will provide larger touch-targets if tapped with touch, as opposed to clicked with a mouse).
We will certainly learn a lot more about Microsoft's app plans for Windows 10 in late April and early May when the company hosts its 2015 Build developer conference in San Francisco.