title: Physical screen size 'detection' based off user agent in PHP/javascript
body: <p>So, there are ways to detect 'mobile' browsers and screen sizes using javascript and php.. however, the screen size is always returned in pixels and mobile can mean anything these days.</p>
  
  <p>I want to be able to know how big a device display is when it's mobile, what with tablets popping up everywhere. The reason for this is because I want to select a stylesheet for devices with small screens and default to the normal stylesheet for everything else. For example, I want an iPad, kindle fire, hp touchpad etc. to display the normal stylesheet but I want a different stylesheet for cellphones or any device that has a display about the size of a human hand.</p>
  
  <p>Now, I'm guessing something to do this doesn't exist but perhaps someone's thought of a better way or knows of a database somewhere that has dimensions for screen sizes somewhere..hmm</p>
  
  <p>..maybe there's a way of finding pixel density and then applying the screen width/height in pixels to this..</p>