The Android OS continues to lead the US smartphone market, but Apple got a big boost in sales in the fourth quarter thanks to the launch of the iPhone 4S. According to the latest data from Nielsen, Android accounted for 46.3 percent of all smartphones in use in the US in Q4, followed by Apple's iOS with 30 percent, Research In Motion's BlackBerry at 14.9 percent and Microsoft's Windows at 5.9 percent. Nokia's Symbian and HP's webOS/Palm each had 1.4 percent of the smartphone market. Among those who acquired a smartphone in the past three months, Android took 51.7 percent of sales in Q4 and Apple had 37 percent, while RIM's share fell to 6 percent. However in December alone, Apple took 44.5 percent of sales in the past three months, up from just 25.1 percent in the three months to October. Of consumers who said in December that they bought an iPhone in the last three months, 57 percent said they bought the latest version, the iPhone 4S. At the end of 2011, a total 46 percent of US mobile users had a smartphone. In Q4, 60 percent of those who said they got a new device within the last three months chose a smartphone over a feature phone.
