Detect ant Route Mobile Phone Traffic

I have a current website [login to view URL] and a mobile version [login to view URL] I am running IIS 6.2 on Windows Server 2012 R2 (latest) I need someone to write code to detect mobile devices and re-route to the mobile website, but allow them to return to access the normal website if they choose. The person MUST HAVE IIS EXPERIENCE as we have tried the simple .htaccess conversion programs and can't get them to work.