How reliable is detecting mobile devices by screen resolution?
This sounds a bit too good to be true, so please tell me if it is.
If I have just one single version of a mobile website (no variations for different devices, just one website for all mobiles), how reliable it is to detect mobile devices by screen resolution?
And simply serve the mobile version if screen resolution is < than say 400px.
NOTE: My question assumes that javascript is enabled. Also,I'm aware there's user agent detection, but I'd like to do without it.
Answer
Javascript mobile device screen detection for height is not reliable at all. The problem is that different browsers use different amounts of 'chrome' and different OS versions use different heights for the system bar. All the detection mechanism report unreliably for height (screen.height, window.outerHeight, window.innerHeight - etc,etc)
Width seems to be most reliable on window.outerWidth across all OS's.
Read a most excellent analytical report here:
http://www.tripleodeon.com/2011/12/first-understand-your-screen/