Slide Over and Split View multitasking for iPad in iOS 9: Explained
Apple calls it Multitasking for iPad. The iPad, of course, has always multitasked at the system level, and over the years has gained background tasks and refresh and other forms of third-party multitasking as well. With iOS 9, however, the iPad is getting more than just the ability to do multiple things at once—it's getting the ability to show multiple apps at once. It's getting Slide Over and Split View.
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