Apple has overtaken Samsung to become the largest mobile phone vendor in the United States for the first time. The Cupertino company captured a record 34% market share during the fourth quarter of 2012 with around 17.7 million devices sold, while Samsung captured 32% with around 16.8 million devices sold.

The latest data from Strategy Analytics shows that U.S. mobile phone shipments grew 4% annually from 50.2 million units in Q4 2011 to 52 million units in Q4 2012. Growth was reportedly driven by a strong demand for 4G smartphones and 3G feature phones.

This solid quarter comes in stark contract to the first three quarters of 2012, which saw mobile phone shipments fall 11% from 186.6 million units in 2011 to 166.9 million units in 2012. Strategy Analytics blames economic uncertainty and tighter carrier upgrade policies for that.

Apple’s share of the market in the fourth quarter rose from 25% with 12.8 million units sold in 2011 to 34% with 17.7 million units sold in 2012. This makes the Cupertino company the largest mobile phone vendor in the U.S., according to Strategy Analytics, a landmark it has reached for the first time.

Apple’s success has been attributed to its popular ecosystem that includes the App Store, generous carrier subsidies, and extensive marketing around the iPhone 5.

Samsung took second place in market share with 32% and 16.8 million units sold. Although it didn’t beat Apple, its share did rise 5 points from 27% a year earlier. Samsung had been the largest cellphone vendor in the U.S. since 2008, and this is the first time it has been knocked off its perch.

LG remains the third largest player in the U.S. with a 9% share of the market after shipping 4.7 million units. The company’s share seems tiny when compared to that of Apple’s and Samsung’s, which highlights just how much of a hold on the market the two companies have. It really is a two horse race at the top.

Both Samsung and LG will be working to grab more market share this year with new Android devices, including a new Optimus G 4G and of course, the Galaxy S IV.

• SourceStrategy Analytics