On a single page you can set individual items to be visible or hidden on mobile and non-mobile devices. For example to make a dynamic banner only visible in desktop (non-mobile) browsers, right-click on that item on the page, select Mobile browsers and then Non-mobile browsers only.
To replace entire pages based on their being accessed from a mobile device, use the If accessed from mobile device... field for a page. If a page is specified there, and this page is being loaded from a mobile device such as a smart phone, VSys Live will show the page you specify instead of this one.
If the mobile page is Hidden, VSys will stay with the current page.