How do I find the virtual viewport/screen width using Javascript?

Question

Is there a consistent way to determine the width of the screen and virtual viewport for mobile devices using Javascript? My target platforms are mobile Safari and Android\'

Answer 1

It may help to set the scale of the viewport to 1.0 using this > tag:

This solved a similar problem for me when when I was creating a responsive HTML/CSS layout for a mobile app (I was using CSS @media queries).