Screen Autorotates on Unity Remote

I'm trying to make a mobile app for an Android device, and I need to lock the screen's rotation. I used

 Screen.orientation = ScreenOrientation.LandscapeLeft;

in the Start() method, but it's rotating anyway. I'm using Unity Remote, so it's possible that that's part of the problem.

Edit: It works after building, but it would be convenient if I could use Unity Remote for this. It's difficult to test when down is always in the same direction.