Microsoft isn't exactly close to surpassing Android or iOS in terms of smartphone sales but they are gaining ground thanks largely in part to BlackBerry's recent downfall. According to recent data published by analytics firm Kantar, Windows Phone claimed 4.1 percent of all smartphone sales in the US during the three month period ending in February. That's up 1.4 percent over the same period a year ago.

For comparison, BlackBerry (formerly RIM) sold 3.6 percent of all smartphones in the US a year ago compared to just 0.7 percent during the most recent period. Symbian dropped from 0.5 percent to 0.1 percent although that's really irrelevant as there's virtually no hope for that OS to be a major contender in the US. Sales of all others decreased from 0.8 percent to 0.4 percent, Kantar noted.

Speaking of the top two operating systems, Android continues to inch ahead of iOS. Google's mobile operating system was responsible for 51.2 percent of all smartphone sales - an increase of 5.8 percent from a year ago. Apple is still holding strong at 43.5 percent but that's down 3.5 percent from the same time last year.

In related news, Verizon Wireless remains the top carrier as they sold 35 percent of all smartphones ending February 2013. AT&T held on to the silver medal with 26.7 percent while Sprint claimed third place with 15 percent of all sales. T-Mobile continues to lag behind with just 9.8 percent although recent deals and the fact that the company is finally getting the iPhone may soon help boost their smartphone sales.