Replace an App using Split View in iOS…
When using an iPad with iOS11 (or better) you are able to use multitasking to have two apps available in Split View.
With Two Apps in Split View drag up to display the Dock. Tap and drag an app from the Dock and move it over the app you want to replace.
(Tap/Click to enlarge the image and run the animation. Use your browser back button to return here).
The Photos app is on the left and Files app on the right.
To replace Files with the Tips app tap and drag Tips onto the right-hand side of the screen.