Mobile Device Detection via User Agent RegEx Varnish

varnish.vcl

   #Mobile detect https://gist.github.com/dalethedeveloper/1503252
    if(req.http.User-Agent ~ ".*(Mobile|iP(hone|od|ad)|Android|BlackBerry|IEMobile|Kindle|NetFront|Silk-Accelerated|(hpw|web)OS|Fennec|Minimo|Opera M(obi|ini)|Blazer|Dolfin|Dolphin|Skyfire|Zune).*")
    {
      set req.http.X-ua = "mobile";
    }else{
      set req.http.X-ua = "desktop";
    }
    
    sub vcl_hash {
    hash_data(req.http.X-ua + ":"  + req.url );
   }