The ability to have multiple windows open simultaneously benefits from larger screen real estate. While having 2 apps open side by side has become common, it is now possible to have 3 or more apps on the screen at the same time.
For more information, refer to the Multi-Window guide.
Drag and Drop
As more devices support multi-window, consider enabling sharing content between and among the visible windows by adding support for drag and drop in your app.
You can help your users make the most of multi-tasking by enabling multiple instances of your app. For example, users can view 2 different websites simultaneously in Samsung Internet browser, compare content across multiple notes in Samsung Note, or copy files from one folder to another in My Files.
For more information, refer to the Multi-instance.