Mozilla's first Firefox 4 beta for mobile is now available to download and test. It?s built on the same technology platform as Firefox for the desktop and optimized for browsing on a mobile phone. Firefox beta for mobile comes with many Firefox desktop features like Firefox Sync, Add-ons and the Awesome Bar.

The major focus of this release was to increase performance and responsiveness, Mozilla said. Two of the big architecture changes are Electrolysis and Layers. The alpha contained Electrolysis which allowed the browser interface to run in a separate process from the one rendering Web content, resulting in a much more responsive browser. This beta brings the Layers pieces which improve overall performance and in graphics areas such as scrolling, zooming and animations. For more technical details, see Mozilla mobile engineer Matt Brubeck?s blog.

Firefox 4 Beta includes Firefox Sync, which allows users to take their browsing history, bookmarks, tabs, passwords and form-fill data with them anywhere so they never have to retype passwords or long URLs again. The Firefox data is completely encrypted end-to-end between the computers.

This release also delivers a rich set of features, including pinch-to-zoom, which is now supported on multitouch-capable devices, and the Awesome Screen, which instantly gives users access to their recent history, bookmarks and tabs just by tapping in the Awesome Bar. See the release notes for a full list of features included in this release.

Developers have the power to use the latest Web technologies like HTML5, CSS and JavaScript to to build fastmobile apps and add-ons.