DrDoc - 4:49 pm on May 31, 2013 (gmt 0)
It was already answered above:
The usual way to detect a Kindle is with the strings "kindle" and "silk", one of which should appear in the UA when Mobile View is on - not a foolproof detection method, but at least you should be able to test that your script is working.
phranque also linked you a useful Google search:
site:webmasterworld.com responsive design - Google Search:
As for other methods, you really have tons of options:
Your current approach is to detect the UA. While it appears to match a wide range of mobile UAs correctly, maintenance is a headache. And, there's always the odd issue of when UA detection falls short (as you have already noticed).
I would research the different methods above and find which one fits you best. Dive in well armed with full knowledge of what your current users look like (devices, browsers, percentages, etc), and which crowd you are attempting to please.
Also -- while you might not like the answer -- getting rid of flash is really a smart decision as it will make your site usable by everyone. Most mobile devices can already handle a regular HTML site quite well. Choose an approach that does not specifically cater to a limited crowd (i.e. mobile users), but rather opens up and improves for everyone (desktop, mobile, tablet, hybrid .. search engines!). You will also find that site maintenance will become much easier.
Just because a business decision was made years ago doesn't mean it was the right decision, nor that it should be ignored when trying to address something seemingly different. Replacing your flash site is simply the best place to start.
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