irule to add string for mobile device

naladar, he has the right idea, that's the first if statement - !([HTTP::uri] contains "requestAgent") - note the !.

peter, your irule worked for me, though I had to make a change to a bit of it.

when HTTP_REQUEST {
  if { !([HTTP::uri] contains "requestAgent") } { 
    if { !([matchclass [HTTP::header "User-Agent"] contains $::MobileAgents]) } {
      HTTP::redirect "https://[HTTP::host][HTTP::uri]?requestAgent=mobile"
    } 
  } 
}

I put quotes around the value after HTTP::redirect, and removed the / between [HTTP::host] and [HTTP::uri], as the URI will always at a minimum contain a /. In general this probably isn't very robust - imagine a user coming in on a mobile device with the url http://example.com/?foo=bar. Your irule will redirect them to http://example.com/?foo=bar?requestAgent=mobile, which will I suppose work for the irule but will confuse your application on the backend.