The split-screen mode makes it easier to multitask. To split screen, simply drag a window all the way to one side of the screen until it snaps into place. Then select another window to fill the other half of your screen. Here's the step-by-step instruction.
Tap on the Overview icon on the bottom launch bar to get into the recent task list. You can see the thumbnails of all running apps here.
Tap and hold a window to trigger the split-screen mode.
Drag a window to the left or right edge of the screen where you'll see a space that can hold the window appears. Drop the window and it will snap into the right position.
You should now see the thumbnails of other windows on the opposite side of the screen.
Tap on another window and it will snap to the other side of the screen. Now, you have two windows side by side.
You can change the width of each window by dragging the divider to the left or right.
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