Phone doesn't show what my unity camera is showing.

As the title says when I’m exporting to my phone I lose some parts from the left side of the screen, so what I did until now to fix this was to move the camera manually in unity to the left so that I could have the screen that i want on phone. Is there any way to avoid this?

Guess you need to make the aspect ratio of the Game view window match the aspect ratio of the phone. There’s a drop-down under the Game tab for this.