Helsinki: Nokia Oyj, the world’s biggest maker of mobile phones, is expanding services, including maps and payment applications to lure customers and combat competitors such as Apple Inc. and Google Inc.

The company opened its map services to application developers to build offerings for its Ovi store. It is already working with Facebook Inc., railway company Deutsche Bahn AG, National Geographic and others on map services, Niklas Savander, executive vice-president for services at the Espoo, Finland-based company, said at the Nokia World conference in Stuttgart on Thursday.

Defending turf: Nokia headquarters at Espoo in Finland. Henrik Kettunen / Bloomberg.

Nokia is extending services to more phone models and courting application developers to distinguish its smart phones from rivals. It has struggled to maintain market share in smart phones against new entrants such as Apple, which has a large developer base in the US. As more and more battles are fought on content, Nokia is defending its share of the $50 billion (Rs2.45 trillion) smart phone market, the industry’s fastest growing segment.

Nokia had 45% of the smart phone market in the second quarter, researcher Gartner Inc. said. That’s down from 62% in 2005. Smart phone sales are estimated to increase 27% to 170 million units bringing in revenue of $57 billion this year, it said.