If you're going to go from this "Mozilla/5.0 (Mobile; Windows Phone 8.1; Android 4.0; ARM; Trident/7.0; Touch; rv:11.0; IEMobile/11.0; BLU; WIN HD W510u) like iPhone OS 7_0_3 Mac OS X AppleWebKit/537 (KHTML, like Gecko) Mobile Safari/537", to something useful, you should probably give the useful one a new name and drop u-a on the drop dead date... That way websites can test the new way with their audience in advance.