As we get closer to the release of the Mango update for Windows Phone 7, website operators will have to make some adjustments in order to accommodate the new version of Internet Explorer 9 that will be included in the update. In the latest Windows Phone 7 developer blog entry, Microsoft's Charles Morris gives those website operators details on the new user-agent string for the mobile version of IE9. Those changes let websites detect when a Windows Phone 7 Mango user is accessing the site with the new version of the browser.
As you might expect this blog entry is a bit on the technical side. Morris describes how the user-string for the new mobile version of IE9 works, saying, "In fact, we can reuse most of the description from the original post announcing the IE9 UA string on Windows." For those of you who run websites, Morris posts what the UA string should be to properly support WP7.
Morris says that while having user-agent features is a good way to identify which browser is accessing your site, he adds that site operators should " ... use feature and behavior detection to detect specific browsers wherever possible." He also says, "If you do decide to use UA detection, we suggest using the 'IEMobile' token to identify Internet Explorer on Windows Phone as a mobile browser." Finally he says that now would be a good time to put in some extra features such as HTML5 video that can be detected on the new mobile version of iE9.