The market for smartphone apps will benefit from growth of nearly 50% in 2011, according to new research.

The International Data Corporation (IDC) Worldwide Quarterly Mobile Phone Tracker estimates that the worldwide smartphone market is expected to increase 49.2% in 2011, growing more than four times faster than the overall mobile phone market. Smartphone vendors will ship more than 450 million smartphones in 2011 compared to the 303.4 million units shipped in 2010.

IDC is predicting that Android will take over as the leading operating system in 2011, but that the Microsoft/Nokia alliance will see Windows Phone growing in popularity to become the number 2 operating system worldwide behind Android by 2015.

According to Ramon Llamas, senior research analyst with IDC's Mobile Devices Technology and Trends team:

"Up until the launch of Windows Phone 7 last year, Microsoft has steadily lost market share while other operating systems have brought forth new and appealing experiences. The new alliance brings together Nokia's hardware capabilities and Windows Phone's differentiated platform. We expect the first devices to launch in 2012. By 2015, IDC expects Windows Phone to be number 2 operating system worldwide behind Android."

The chart predicts that BlackBerry and iOS will maintain their market share but Symbian's share drops out, which is only to be expected given the news we reported in Nokia confirms that Symbian phones will just fade away.