AspNetCore.Docs/aspnet/whitepapers/add-mobile-pages-to-your-aspnet-web-forms-mvc-application/samples/sample15.xml

<redirect firstRequestOnly="true"
          mobileHomePageUrl="~/Mobile/Default.aspx"
          timeout="20"
          devicesFile="~/App_Data/Devices.dat"
          mobilePagesRegex="/Mobile/" />