Tokyo-headquartered online game publisher Nexon has posted increases in revenue and profits year-over-year, thanks to the company's focus on the free-to-play business model.



The company said it saw strong growth for its free-to-play and online games in China and Korea during the quarter, although this was slightly offset by an underwhelming performance for its games on North America. This, it said, was a result of "certain operational challenges" in the region.



Even with these issues, Nexon still managed to exceed its expected performance for the first quarter.



Nexon said that a number of the titles it launched in 2011, including Cyphers, SD Three Kingdoms and Mabinogi Heroes, maintained strong growth throughout this fiscal year's first quarter. In particular, iOS and Android game Kartrider Rush has now been downloaded 8.2 million times to date.



Although the company's monthly active user count declined slightly to 82.8 million from 86.2 million year-over-year, it saw its paying user rate increase to 10.9 percent of its total users paying, from 8.3 percent year-over-year.



For the quarter ended March 31, 2012, Nexon posted revenues of 30.4 billion yen ($381.1 million), up 46 percent compared to 20.8 billion ($261.1 million) year-over-year. Of this total figure, 15.2 billion yen ($190.4 million) -- around half -- came from China, while 8.9 billion yen ($111.1 million) came from Korea. In comparison, 1.4 billion yen ($17.5 million) came from North America.



The company posted quarterly profits of 12.4 billion yen ($155.3 million), up 63 percent compared to 7.6 billion yen ($95.2 million) year-over-year.