On the PC version page (http://pc_url), add:
<link rel= "Alternate" media= "only screens and (max-width:640px)" href= "Http://pc_url" >
On the mobile page (Http://mobile_url), the required comments should be:
<link rel= "canonical" Href= "Http://mobile_url" >
The previous META tag (mobile agent) will continue, but we recommend using the HTMAL5 language to make mobile pages with the latest scheme for jump adaptation, other such as the XML language mobile page jump adaptation, need to continue to use the previous meta tag way:
<meta name= "mobile-agent" content= "FORMAT=[WML|XHTML|HTML5"; Url=mobile_url ">
HTML5 new mobile adaptation of the text, this is mainly for Baidu and other search engine crawl to the site's mobile URL is what, not automatically when the device switch to the phone automatically jump. JS is also required for automatic jump.
Reference: http://www.cnblogs.com/osfipin/p/5852037.html
HTML5 Mobile Adaptation notation