TESTING Differentiation of iPhone models – by window.devicePixelRatio

Using

_gaq.push(['_setCustomVar',
1, // This custom var is set to slot #1. Required parameter.
'Device Pixel Ratio', // category
window.devicePixelRatio, // This value of the custom variable
2 // Sets the scope to session-level.

Different iPhones and  different iPads all have the same user agent – and unfortunately a bit of an odd pixel size reporting – this is frustrating in that if you are testing, or simply curious, its nearly impossible to tell which models are more popular.

Although the iOS is different – 4,4s and 5 can all have the same OS, but the resolution has changed in each – this may or may not work however – I will update later.

Ooops – ran out of custom vars, not really using them so will disable them for a while! 

Thanks to @danbarker for the suggestion!

Reference – https://developers.google.com/analytics/devguides/collection/gajs/gaTrackingCustomVariables