Usage of Opera Mini, the Web browser for mobile phones is growing worldwide, according to Opera Software. With more than 15 million cumulative users, the company says Opera Mini is the most popular downloadable Java software for mobile phones.

The target market for this software is fueled by 1.8 billion Java technology-enabled mobile handsets. People in Russia and the United States are the most prolific users of Opera Mini, with the Chinese a close third. In total, more than 5,2 billion Web pages have been viewed with the mobile browser from Opera Software.

Opera Mini is available for free and can be used in any Java technology-enabled. Web pages are compressed on a remote server and delivered to the phone for fast and Web browsing.

But things don't stop here. Enhanced navigation is the next step in the evolution of mobile Web browsing and that's what Opera's developers are exploring for the next version of Opera Mini. Opera Software is inviting people to sign up for testing the beta version of the upcoming Opera Mini.

Release date is not yet announced, but people will be able to test the new version and submit comments and faults.