Microsoft has a big presence at the Mobile World Congress this year, and has announced several new cool devices such as the Lumia 640 and 640 XL and a cross-platform foldable Bluetooth keyboard. On the software front, they have shown off Spartan for Windows 10 phones, as well as the new Bing Maps app and new features that will come in the next big update to the touch-centric Office apps.
Microsoft also held an event called "First look at the Windows 10 Universal App Platform," which was not live streamed, and offers a more detailed look at the company's "One Windows" strategy, an effort to jumpstart the development of apps that work well across a wide range of devices and with different forms of input.
Microsoft's Kevin Gallo explains that the idea of Windows 10 is to have a unified operating system core that allows developers to create apps that have "one set of business logic and one UI." These will be accessible via a unified Store in the form of a single package, and developers can use extension development kits to add device-specific functionality on top of that single binary.
This means universal apps will have a similar look and feel, but will feature a screen layout and user controls that make sense for the device you are using, something called "Adaptive UX."
"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).
Microsoft officials at the event have also confirmed that the Project Spartan web browser, which is also a universal app, will be available with the next preview build of Windows 10. We will likely learn more about Microsoft's new app strategy at the Build 2015 conference in San Francisco.
Source: Windows Blog