Opera Software reported a surprise third-quarter net loss of about $2.1 million even though revenue was up.

Hit by high operating costs, the Norwegian browser maker also said its third-quarter revenue from Internet Devices unit fell 5 percent.

However, the company said it remains positive about its growth prospects, citing heightened interest among operators and mobile OEMs for its solutions as Web browsers become a common component in more devices.

The company says 55 new mobile phones with Opera preinstalled were announced in the quarter, including 25 for Opera Mobile and 30 for Opera Mini. The number of mobile phones shipped with Opera Mobile preinstalled was 4.5 million in the third quarter.