Mozilla has released an early version of Firefox for the mobile and its actual name is Fennec. The software is in its Alfa stage and is available for download at the following link: Download Firefox Android.
The newly released Firefox is compatible with Android and Maemo platforms. The Android Firefox is optimized for Motorola’s Droid and didn’t work very well on the Google Nexus One.
Fennec comes with Bookmarks (including tags), a smart URL bar, tabbed browsing with thumbnail images, integrated Web search (built into the URL bar) and many other features an internet browser should have.
To install Fennek on Android, copy the .apk file into your phone memory and complete the installation using the file explorer application (GeckoApp).
You can also try Fennec on your PC, download it using the link here.