Some 472 million smartphones were sold in 2011, new figures show.
Overall, they accounted for 31 per cent of all mobile phone sales last year, which was a 58 per cent increase on 2010's total, Gartner stated.
In the final quarter of 2011, 149 million smartphones were sold to end users - a 47.3 per cent increase on the figure from the same period the year before.
The increases were driven by sales of Apple iPhones, with the company becoming the world's third-largest mobile phone vendor behind Nokia and Samsung and the world's top smartphone vendor.
Roberta Cozza, principal research analyst at Gartner, stated: "In Western Europe the spike in iPhone sales in the fourth quarter saved the overall smartphone market after two consecutive quarters of slow sales."
Mobile data traffic is also on the up, according to the Cisco Visual Networking Index Global Mobile Data Traffic Forecast Update.
It revealed a 2.3-fold growth in the sector in 2011, which was a better-than-expected performance.