Mozilla has released a new beta of Firefox 4 for Mobile. The new version resolves several long-standing problems with the Android port, finally making it viable for day-to-day use. The new version also brings a minor theming refresh that improves the application's look and feel.

In previous versions of Firefox for Android, the installed application used over 40MB of storage space and couldn't be permanently moved to the SD card in its entirety due to the manner in which Android loads native libraries. Mozilla has done a lot of work to address this issue, including making a custom dynamic linker that can load the native libraries directly from the compressed APK file. In the new beta, Firefox for Android requires only 17MB of storage capacity and can optionally run entirely from an SD card.

The browser's performance has also improved considerably. Page scrolling is consistently responsive, even while pages are loading—an area where it used to struggle in previous versions. The user interface is also smoother, with virtually no lag when navigating between the various settings panels. Features like the AwesomeBar work exceptionally well and no longer suffer from any sluggishness. Due to Mozilla's aggressive JavaScript optimization efforts, the browser's JavaScript performance is now fully competitive with that of Google's native Android browser. Firefox even comes out ahead in some benchmarks.

The user interface on Android has been refined and slimmed down a little bit. It still doesn't adopt the platform's native look and feel, but it doesn't look out of place. The theming choices that Mozilla has made in the new design are good and will likely be a good fit with the broad spectrum of custom Android styles that are used by various handset makers. The whole user experience feels a bit less cluttered.

Firefox for Android has come a long way and has finally achieved a level of smoothness that makes it suitable for day-to-day use. Features like add-on support and compatibility with Firefox Sync are compelling enough to make it worth using. The only area where the browser is still weak is text handling. When you zoom in, the browser doesn't automatically reflow text to fit the screen. This negatively impacts readability and makes the browser uncomfortable for reading articles and other long-form text. For now, the best way to handle those things is to use the Readability add-on.

Mozilla is planning to continue its focus on performance improvements in future versions. The developers want to add hardware accelerated rendering and make scrolling even smoother. Another goal is to add support for the HTML5 video element.

Users can download Firefox Mobile from Mozilla's website (phone version). For additional details you can refer to the official release notes.