Will WP7 trounce the iPhone in 2015?

Sales of Windows Phone 7 devices have thus far been rather underwhelming. But analysts at IDC believe Microsoft’s WP7 platform, combined with Nokia’s hardware expertise, will help the rapidly evolving OS outpace Apple’s iPhone.

According to senior IDC researcher Ramon Llamas, WP7 is likely to benefit from Nokia’s “support, scope, and breadth” within markets where the Finnish-based company has historically maintained a strong presence.

However, Llamas acknowledged WP7 will initially only capture a “small share of the market,” as Mango-enabled devices are slated to hit store shelves in late 2011.

“Nevertheless, assuming Nokia’s transition to Windows Phone goes smoothly, the OS is expected to defend a number 2 rank and more than 20% share in 2015,” he predicted.

And Apple’s iOS?

Well, IDC exepcts the iPhone to remain a primary force in the mobile market until at least 2015. After an initial “explosive growth period,” iOS is projected to grow at a more modest pace as the smartphone market matures and diversifies. 

Although a slight market share decline is expected, IDC still sees significant overall shipment volume growth through the end of 2015, with market share estimated to decrease slightly to 16.9% from 18.2% in 2011.

Meanwhile, Google’s Android – which outpaced Symbian as the leading operating system worldwide in Q4 2010 – remains on track to claim more than 40% of the market in the second half of 2011 and 43.8% by 2015.

“A significant and growing list of vendors who have made Android the cornerstone of their respective smartphone strategies is propelling the growth of Android,” Llamas noted.

Finally, BlackBerry OS is likely to maintain its position as a Top 4 smartphone operating system. Yet, similar to Apple’s iOS, RIM’s BB will experience market share decline – even as shipment volumes grow.