You can debug using Firebug on your iOS device.
First, open Safari on your mobile device.
Next, create a bookmark in Safari on your iOS device for any webpage, and name that bookmark “Firebug.”
Following this, launch Safari and edit the Firebug bookmark, replacing the URL with the above text. Hit “Done,” and the bookmarklet should be created and ready to use.
In order to launch the Firebug console, visit a website on your iOS device and, once the website has loaded, open your Bookmarks in Safari and touch Firebug. After a few moments, the console should appear at the bottom of the webpage (as you can see in the image).