Mobile Sites / Useragent detection

[AlecPR]

I've got a question about how search engines declare that they're mobile browsers...

Our website is based on wordpress, and uses the caching plugin W3TC to send a different site template to mobile useragents - i believe from the HTTP useragent string; (the same content is served on every page whether it's a desktop or mobile - just different themes).

After having this mobile site online for a few months, we're a little confused as to why google still shows the instant preview of the desktop version for mobile users, and it doesn't show the little mobile phone icon in our SERPs for mobile devices (it's as if it doesn't realise the mobile site exists).

I was reading today that the "old" method of serving different content based on the browser is to use the HTTP useragent string; and there's a "new" object checking method which is more robust (although I can't find a lot of information about it).

Can anyone explain the "new" method? Would this be the reason that google is so far ignorant of our mobile site?

[RobertFisher]

Alan,

Full disclosure, I am not a coder but have several that speak to me daily I believe this will help you out: It is around using the navigator object in JS for detection. Here are a couple of links with possible answers for you:

http://www.javascriptkit.com/javatutors/objdetect2.shtml and http://www.javascriptkit.com/javatutors/navigator.shtml

and http://wurfl.sourceforge.net/njava/

These are from two different sites, hope you find a bit of help here,

Best