Although you can copy and paste details and formulas between apps, I would find it very useful to copy entire screens from one app to another.
I am sure I cannot be the only one!
The blog by Emma Cooper, Program Manager II, Tuesday, April 10, 2018 says,
Copy and pasting of screens across apps is currently not available. All the controls on the screen can be copied and pasted, but if you attempt to paste the screen, it will not work. A workaround is to add a new screen in your target app and copy all the controls from the screen of the other app to paste there. You will also need to copy any expressions in the OnVisible or OnHidden properties of the screen control. This is something that is planned to be addressed in the future.
When is this future?
Copying controls would be so much more useful if the controls could retain their x and y values when pasted into the new app/screen. Moving/placing the controls is a pain after pasting.