Can't setup iPhone view

I am putting iPhone screen size in vizualisation area properties (e.g., 640x1136 for iPhone SE), adjust the vizualisations, but when I open the view I created on an iPhone, I see less then quarter of the screen I created, I have to scroll to the side and to the bottom to see everything.

I don't understand why, can someone help? Am I doint something wrong?

I don't understand what is the point of adjustable viz area then if it in the end looks out of proportion.

(2) Answers