Separate mobile and desktop ads

app/views/layouts/_cdn.html.erb

@@ -12,5 +12,8 @@
 <script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.js"></script>
 <script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.map"></script>
 
+<!--Mobile and tablet detection-->
+<script type='text/javascript' src="//wurfl.io/wurfl.js"></script>
+
 <style>
 </style>

app/views/layouts/_rsidebar.html.erb

@@ -1,6 +1,17 @@
 <% if Rails.env.production? %>
     <div class="ad">
         <script type="text/javascript">
+        if(WURFL.is_mobile){
+            //Mobile and tablet ad
+            (function(){
+                CHITIKA = window.CHITIKA ? window.CHITIKA : {'units' : []};
+                CHITIKA.publisher = 'cwimer';
+                var s = document.createElement('script');
+                s.src = '//cdn.chitika.net/getads.js';
+                try { document.getElementsByTagName('head')[0].appendChild(s); } catch(e) { document.write(s.outerHTML);}
+            }())
+        } else {
+            //Desktop ad
             (function (){
                 if(window.CHITIKA===undefined) {window.CHITIKA = {'units' :[]};};
                 var unit = {"calltype":"async[2]","publisher":"cwimer","width":120,"height":600,"sid":"Chitika Default"};
@@ -8,6 +19,7 @@
                 window.CHITIKA.units.push(unit);
                 document.write('<div id="chitikaAdBlock-' + placement_id + '"></div>');
             }());
+        }
         </script>
         <script type="text/javascript" src="//cdn.chitika.net/getads.js" async></script>
     </div>