Nokia's new Chief Executive Stephen Elop (L) shakes hands with Nokia's Chairman of the Board Jorma Ollila during a news conference in Espoo Finland, September 10, 2010
It is official. Nokia will be adopting Microsoft's Windows Phone 7 as its new smartphone operating system, a move that could be the beginning of a new era for the Finnish mobile giant in its efforts to regain smartphone share in U.S.. Reuters

Nokia (NYSE: NOK), the ailing Finnish mobile products maker, will add tablets to new smartphones as part of its turnaround, Chairman Jorma Ollila said.

Besides betting the company on a new alliance with Microsoft (Nasdaq: MSFT), the world's biggest software company, to race its Lumia smartphones into the market with a Microsoft OS, tablets will come, too, Ollila told the Financial Times.

Tablets are important, the veteran Nokia executive said, a few days before he retires after 27 years at the company, which he transformed from a dingy maker of boots into the No. 1 mobile phone maker.

There will be different hybrids, different form factors [handset designs] in the future, Ollila, 61, told the FT. He didn't provide descriptions.

As CEO, from 1992 to 2006, Ollila's leadership made Nokia the top mobile phone maker, a rank it ceded last quarter to Samsung Electronics (Pink: SSNLF). He was succeeded by Stephen Elop, 48, a former Microsoft VP, who has scrapped the venerable Symbian OS for Windows and is trying to recover share and profits.

At the International Consumer Electronics Show in January, Elop appeared with Microsoft CEO Steve Ballmer and with Paul Jacobs, CEO of Qualcomm (Nasdaq: QCOM), the biggest designer of mobile chips, to say Nokia's turnaround would depend on their products.

In his farewell interview, Ollila said the company was too slow to appreciate the impact Apple (Nasdaq: AAPL), the world's most valuable technology company, would have on the development of the smartphone sector.

The competitors were faster, he said.

Nokia shares closed Thursday at $3.54, down 4 cents, bringing the company's market value to $13.26 billion. By contrast, Apple's market value is $543.2 billion.