You can view any website with any platform which has a browser and, providing the website has been designed to comply with the browser, there should be no issue.
Javascript and flash can causes issues on certain mobile devices though, so test first if you feel this type of surfer is common/important etc.
As for sharing the URL by email, that is done in code as you would do on a website (regardless of browser because ultimately they are still viewing a website). As for third party plugins for SMS, it first depends on the language/technology you are using as to what service(s) are available. EDIT: You could try http://mashable.com/2008/04/19/send-text-messages/ to give you an idea.
If you want to just detect the device, then in ASP.NET (C#) you can do something in the PageLoad() method
if (Request.Browser.IsMobileDevice)
{
Response.Redirect("~/mobile.aspx");
}