Today, Microsoft announced the release of preview SDK for Surface Duo device that will allow developer to create dual-screen experiences. Microsoft will also be releasing a preview SDK for Windows 10X next month. In addition to the preview SDK, Microsoft today released a documentation for developers that describes functionality and guidance for developing experiences for dual-screen devices. Microsoft recommends developers to support the following layouts:
- By default, apps open in a maximized state and occupy a single screen. In double screen postures, users can run two apps beside each other to simultaneously compare, consume, or cross-reference content.
- Supported by default. If your app was designed to handle different screen sizes and portrait and landscape orientations as described earlier, there’s nothing more you need to do.
- When the device is in a two screen posture (double portrait or double landscape), users can extend a single app across both screens, allowing more space for content. The user is responsible for spanning the app, it’s not a state the app enters programmatically.
- Support is optional. Spanned mode is unique to dual-screen devices. If you don’t make any modifications to your app, it will behave as if it is being displayed across one large screen. However, you can implement a range of layout optimizations to make your app take advantage of the unique features of dual-screen devices. These are covered in more detail later in this article.
- Single-Full Screen
- This is similar to the default layout, except the system UI (Task Bar, System Tray, App Bar, App Title) are hidden to create a fully immersive experience, ideal for games and video playback.
- Support is optional. You can use available APIs to put your app in full screen mode.
- Spanned-Full Screen
- You can programmatically expand your app to use full screen mode when spanned. If an app that is displayed on a single screen in full screen mode is spanned by the user, it will remain full screen.
- Support is optional. Consider the benefit of full screen in a spanned mode as well as single screen.
All dual-screen devices can fold, flip, and rotate. Both screens can be used as displays, or one screen may act as a keyboard. The different form factors support a wide variety of activities and allow the user to fit the device to their situation. Even though all the existing apps will work in dual-screen devices without any modifications, developers are expected to fully embrace dual-screen functionalities by making changes to their apps.