The
IE10 user agent string was originally introduced in the first platform preview of IE10. In Windows 8 Release Preview we made two additions to aid server-side feature detection.
The first addition enables detecting whether a machine has touch-capable hardware via a new Touch token. Using this token you can present a touch-friendly version of your site to users with touch-capable hardware (typically, in the case where your normal site is not touch-friendly). Keep in mind that users with touch-capable hardware may also use a mouse and keyboard. You can see where this token fits into the user agent string in the examples below.
