How to Use Three Apps at Once on the iPad in iOS 11
iOS 11 supercharges the multitasking prowess of the iPad by allowing you to use three apps at a time, rather than just a pair. This means it's easier to change the song you're listening to in Music, reply to a tweet or check how long it will take to get to your next appointment.
The third app appears in a Slide Over pane, and the big trick is getting a feel for how to move it and dismiss it. Here's how to pull up those extra apps when you need them, and dismiss them to get back to work.
1. After using the Dock to split your screen between two apps, swipe up from the bottom of the screen.
2. Drag an app icon to the black bar between your apps.
3. Release the icon.
4. Drag the Slide Over app by the bar at the top to move it horizontally.
5. Flick the Slide Over app to the nearest side to dismiss it.