I guess you’re the author and not a native English speaker, so here’s a language tip. Nice article, but harder to understand than needed because it uses “rotation” for both the direction the phone is pointing at and changes to it.

The article would be easier to read if it used “orientation” for the former (https://en.wikipedia.org/wiki/Rotation: “Rotation is the circular movement of an object around an axis of rotation” and (under “See also” “Orientation (geometry) – Notion of pointing in a direction”)