49% of smartphones sold around the world will be running Android at the end of 2012, according to a report from Gartner.

Total worldwide smartphone sales are expected to reach 468 million units this year, which is 57.7% up year-on-year. Android is forecast to have 38.5% of those sales, making it the world’s most popular mobile operating system.

Sales of devices that have an operating system open to app developers - generally ‘smart’ mobile phones - are expected to account for 26% of all mobile handset sales this year, rising to 47% by 2015.

Gartner predicts that Apple’s iOS will remain in second place for several years, despite its market share slipping slightly from next year, while the Nokia/Microsoft partnership will see Windows Phone moving to capture the third-largest worldwide share by 2013.

Carolina Milanesi, research vice president at Gartner, said “The growth in sales of media tablets expected in 2011 and future years will widen the ecosystems that open OS communications devices have created. This will, by and large, function more as a driver than an inhibitor for sales of open OS devices. Consumers who already own an open OS communications device will be drawn to media tablets and more often than not, to media tablets that share the same OS as their smartphone. This allows consumers to be able to share the same experience across devices as well as apps, settings or game scores. At the same time, tablet users who don’t own a smartphone could be prompted to adopt one to be able to share the experience they have on their tablets.”

Worldwide ‘Open OS’ device sales to end users (thousands of units)

Source: Gartner (April 2011)