"We have no plans to release the full Firefox browser for Apple iOS devices. The current iOS SDK agreement forbids apps like Firefox that include their own compilers and interpreters.
It's technically possible to port Firefox to iOS, and some people have done some work on that in their spare time. But unless Apple removes these restrictions, Mozilla will not spend time and money on this project. The development would likely violate the SDK agreement, and it would not be distributable to non-jailbreak iOS users."
This has pretty much been the standard Mozilla response; however, its interesting to note that some work has been done on the port. Currently, Mozilla's only presence on the iPhone is Firefox Home, an app which provides access to your desktop history, bookmarks, and open tabs.
Read More [via TechCrunch]