Samsung Galaxy Note 5 Manual page 63

48 Prologue
Minimized apps
Quicker Way of Running Multi-Window
If you only want to use apps that are already running in Multi Window, you can
do this more quickly. Tap the Recents Apps button. Tap the Multi Window icon
on any running app. That app switches to Multi Window mode and displays in
the top-half of the screen. Next, tap a second app to run in the bottom half of
the screen. Remember that not all apps support Multi Window, so some apps
might not have the Multi Window icon.
Tap to select app for Multi Window.
App in a pop-up
window
Choose a second app.