Another awkward aspect of Multi Window: The keyboard doesn't always stay on top as you open floating windows. Opening a new app in a floating window can cause that window to overlap the keyboard. There is a solution, but it's not appealing: If you tap and hold the Settings key or Microphone key on the keyboard (you'll see one or the other, not both, to the left of the spacebar), a Keyboard Options button appears. Tap it to display three options, and choose the Floating option. When you do this, the keyboard shrinks to an unreasonably small size, but the overlapping issue does go away. As I said, this is not an appealing solution.
The Multi Window feature works only with apps you dock to its Multi Window bar, which you open by swiping from the screen's right edge. Basically, it's a clone of Windows 8's App bar, which is on the left side of a PC's screen. But the Note Pro continues to use Android's standard methods for opening apps -- going to the Apps screen from the home page or using the Running Apps bar invoked from the Multitasking button. If you use those methods, you get only full-screen views of apps, even those docked to the Multi Window bar. It's a bit confusing to have these multiple methods and multiple display results. (The previous Multi Window had no such slide-out bar; instead, it used an icon in each app to split the screen or go back to full screen. It was a better approach for a tablet.)
The Multi Window feature has an option to minimize an app to a circular button that you can move anywhere you want onscreen. That sounds like a nice idea, except these buttons overlay whatever is running, so you'll frequently need to move them out of the way. There's no place to dock a minimized window so that it's always out of the way, and closing a minimized window means long-tapping the icon, moving the window so that you can see the Close button, and tapping that Close button. There should be a simpler way to hide or close them.
To me, the previous generation of Multi Windows made more sense: It split the window into side-by-side panels, similar to what Windows 8 allows in its Metro UI, keeping text readable and incurring no performance penalties. In trying to have Multi Window act more like a PC than a tablet, Samsung made it less usable in practice, if not in theory.
When running with Multi Window enabled, the Note Pro's floating windows can overlap the tapped window. Here, you can see the Calculator app is above the active Calendar app, obscuring the onscreen keyboard.
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