diff --git a/docs/phone_test.html b/docs/phone_test.html
index f280db2..693a75a 100644
--- a/docs/phone_test.html
+++ b/docs/phone_test.html
@@ -69,6 +69,12 @@
 
             </div>
         </div>
+        <div class="grid-cell" style="font-size: 12px; max-width: 300px; word-break: break-all;" id="userAgent"></div>
+
+        <script>
+        document.getElementById('userAgent').textContent = "User agent: " + navigator.userAgent;
+        </script>
+        
     </div>
 </body>