Opera Software, the world's largest mobile browser firm, has bought Australian web-based email provider FastMail.FM, aiming to expand its own messaging offering to wireless devices.

Norway-based Opera, whose wireless browser is more used than Apple's iPhone browser, has had its own email offering for years.

Opera declined to comment on the price of FastMail, which has around 250,000 active users.

Rolf Assev, Opera's strategy chief, said the acquisition would give the company better knowledge of Web-based email systems, and enable expanding its current email offering.

Because many people will first experience the Web on a mobile device, it makes sense to extend our messaging capabilities to all devices, Assev told Reuters.

He said the company was not yet prepared to comment on specific product plans in the area. (Reporting by Tarmo Virki; Editing by Erica Billingham)

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