Annoying Zooming on Mobile

How do I prevent the mobile site from zooming when selecting a form field?

I have a very simple page with one input field but when you click into the input field to enter a value it zooms in.

Update: Fixed with a meta tag …

<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0,user-scalable=0"/>