Double window lets you take the best out of the screen allowing you to access two terminal windows at the same time. To activate it, open the Terminal Menu, go to the Tools tab and touch on Double Window.
It will divide your screen in half, offering you two working windows. You can use the double window either in landscape or portrait orientation.
When you execute a command its result will be shown in the active window. To work on the other window or change the active window, just tap/click on the window you wish to work on.
To deactivate it, go to Tools tab, and touch on Single Window.