Madhava Enros and Sean Martell have been working on creating a default theme for the Fennec web browser (“Fennec” is the code name for Mobile Firefox). Madhava writes, “We’re trying for something that nods back in the direction of Firefox on the desktop while still striking out in a direction that’s appropriate for a small-screen finger-directed device. [Sean]‘s posted some recent work to his blog, and he’ll be posting more there as we go. This is an effort still very much in progress, so please jump in with your suggestions. There’s a Fennec UI discussion thread ripe for contribution.” For more information and some mockups of the theme, see Madhava’s blog post.

The recent release of Fennec (the code name for Mobile Firefox) Milestone 7 included the revolutionary addition of an Add-ons manager for the mobile browser. Mark Finkle has written a detailed post that talks about developing add-ons for Fennec, explaining its various similarities and differences to Firefox. “Fennec is a XULRunner application and gives extension developers access to the same underlying XPCOM system that is used in Firefox. The process of building extensions is the same as for any other Mozilla based application.”

There are significant differences, as well. “Fennec is not Firefox. It is a completely different application. Fennec’s UI is also very different than Firefox. This means you can’t just plop a Firefox (or Thunderbird or Songbird) extension into Fennec and expect anything to work. There are some basic things an extension developer will need to handle when making or porting extensions to Fennec.” These differences include: a different application id, a very different XUL UI, and different JavaScript objects and functions in the UI code among other things.

Mark suggests that currently the best way to figure out what’s available is to look at the source code. If you have questions, jump into Mozilla IRC’s #mobile channel, and someone there should be able to help you out. Mark also includes some example Fennec extensions, which you can find linked in his blog post.