Tap the Recent Apps Button . A screen opens and displays
screenshot tabs of all of the apps (and websites) that are currently
open.
Tap the app you want to use, tap the Close icon on the app to close
it, or tap the Back Button
to return to the current screen.
If the app's titlebar has the Dual window icon , you can tap it
to set it as the first window, tap Dual window, then tap the app you want in the second window.
Swipe up or down to view the entire stack of open apps.
Flick an app icon to the right or left to close the app and remove it from the list.
Tap an app to use it.
Tap here to close this app.