Power Apps Code View is very handy to copy Apps / Screens / Controls

Simplifying copy and paste

In the Power Apps studio, for any control, you have a single Copy button to copy the code. Also, there is a button to View Code option as well.

Code format improvement:

We can combine different screens in a single code snippet – so you can save your own templates to quickly start new apps.

Above two options are very useful to take back of your entire app code.