Android 4.1.2 upgrade for the Galaxy Note 10.1 comes with a new features which we haven't seen in Android yet. Apps in the tablet can now be run in multi-window, similar to Microsoft Windows OS. You can run up to 16 multiwindow-enabled Android apps at once, thanks to Samsung's updated TouchWiz UI.
Multiwindow apps can be launched either in the normal manner, from the homescreen or All Apps screens, or from a pop-open "multi window apps tray" conveniently located at the bottom of any screen. The apps tray opens up when you tap the up-arrow in the middle of the screen's lower panel.
A pair of buttons located in the lower-left of the apps tray (illustrated on the right) determines whether the apps launched from the tray start in dual-view or cascade-view.
Source: InformationWeek