How is the design for Android applications created?

Question

Android

The question is not exact and not specific, but it's interesting how the design and all graphics are created for Android applications, NOT games.
Many applications have their own style, creative buttons, views, and how is it all created?
Directly into Android Studio with built-in tools or something like in Photoshop and then transferred to Android?

Answer 1

The designer, as usual, draws a layout in Photoshop, and then the sobbing programmer tries to write an xml layout that repeats this design.

Answer 2

have your own style, creative buttons, views

And then users swear at non-standard design.
Use ready-made Google patterns built into AndroidStudio. Become a cool application with a large turnover - stir up something complicated already.