According to a report from YP, 30% of their searches were done on mobile devices. The category with the highest growth in mobile searches was "Industrial Manufacturing" -- which kinda surprised me. 

If your website (or one of your clients' websites) is in one of the categories that sees a lot of mobile traffic (or if you're just planning ahead), it's worth reviewing your site to make sure that the relevant content is easily accessible on mobile devices like smartphones and tablets. If you're not planning for mobile users, you might be missing something important.

I've run into a number of occasions where restaurants (for example) had some of the most important content on PDF or even within a Flash UI ... Sometimes these things are relatively easy to tide over with tweaks, so don't assume that things are lost without a full redesign, try it out on a smartphone and work out what needs to be done!

FWIW our recommendations in this area are at https://developers.google.com/webmasters/smartphone-sites/

The link below is the PDF -- it looks like that's the only version available :-/
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