Favorite guide how to make the [mobile browser] enter the [www url] to automatically jump to the [mobile edition] page!

For more information, see [mobile browsers] and enter the [www website] to automatically jump to the [mobile edition] page !! For example, if you enter www.sina.com.cn in the mobile browser, the browser automatically jumps to 3g.sina.com.cn, online and other favorites please go to the [mobile browser] and enter the [www url] to automatically jump to the [mobile edition] page !!
How to enable the mobile browser to enter the www url to automatically jump to the mobile page

For example, if you enter www.sina.com.cn in the mobile browser, the browser will automatically jump to 3g.sina.com.cn !!
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Client agent judgment
ISP judgment
Determine whether the client can support features of certain mobile phones (through js and so on)
......

But I can tell you that none of the above is accurate. it is best to make a button for the customer to choose.

BTW: for some time in the past two years, I used x64 firefox (PC) to access the Sina homepage. I always automatically jumped to the wap version and didn't return any settings, which made me think Sina is very junk, it will be fixed in about a month ......
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Let's make multiple functions that you can choose from !! The default version is pc !! Judging the browser ID is also a good way !!