IDC predicts that Windows Phone will surge ahead to become the number-two smartphone operating system by 2015 behind Google Android. That forecast would push Apple's iPhone down to third position, followed by BlackBerry in fourth in 2015, the market research firm said.
Windows Phone will grow, IDC said, because of the alliance forged between the world's largest mobile phone maker, Nokia, and software powerhouse Microsoft.
"The new alliance brings together Nokia's hardware capabilities and Windows Phone's differentiated platform," said Ramon Llamas, an IDC analyst. Many analyst firms, including IDC and Gartner, had predicted last year that Windows Phone without Nokia would only reach 5 to 10 percent market share in coming years.
IDC expects the first devices from the new Nokia/Microsoft alliance to launch in 2012. "By 2015, IDC expects Windows Phone to be the number-two operating system worldwide behind Android," Llamas said.
In 2011, IDC expects Android to secure the top spot for all 12 months of the year, after pushing into top territory late in 2010. Android will secure nearly 40 percent of the smartphone operating system market in 2011, IDC predicted, and then move to 45 percent in 2015. Symbian, Nokia's current OS, will retreat to second place with nearly 21 percent in 2011, to zero by 2015, since Symbian phones will no longer be produced sometime after 2012.
Apple's iOS will be in third position globally for all of 2011, with nearly 15.7 percent of the market, falling to 15.3 percent of the market in 2015. Apple will still sell 19 percent more smartphones each year, however, as the smartphone market expands.
BlackBerry, the smartphone from Research in Motion, will be in fourth position for all of 2011 with 14.9 percent share of the market, dropping to 13.7 percent share in 2015. BlackBerry will still grow by 17 percent each year.
Windows Phone 7 and Windows Mobile, the older Microsoft OS, will take 5.5 percent of the market in 2011, but Windows Phone will surge to nearly 21 percent in 2015, an annual growth rate of 67 percent, IDC said.
Overall, smartphones won't grow quite as fast in 2011 as in 2010, IDC noted. Growth in smartphones globally will be 49.2 percent, IDC said. Vendors will ship more than 450 million smartphones in 2011, compared with 303.4 million shipped in 2010, IDC added.
Part of the reason for the fast growth in 2010 was that buyers held off mobile phone purchases during the 2009 economic downturn, said Kevin Restivo, also an IDC analyst. "The expected market growth for 2011, while still notable, will taper off somewhat from what we saw in 2010."