Opera has a long-standing partnership with Nokia to provide a browser for its phones, it used to be Opera Mini on Series 40 nowadays it’s the full-fledged Opera Mobile on the Nokia X platform.
Opera will be the default browser on Nokia X phones, starting with the new Nokia X2, and it’s available for free download for current X owners.

Opera is now based on Blink but adds Opera’s traditional strengths including Turbo and Speed Dial. There’s also the Discover features, which finds fresh content sorted by country and topic.