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What: Shares of wireless carrier MetroPCS (NYSE: PCS) popped today, up by as much as 14% after the company reported earnings this morning.

So what: Fourth-quarter revenue was up 16% to $1.2 billion, leading to diluted earnings per share of $0.25. The company also tacked on 197,000 in net subscriber additions in the quarter, with full-year total subscriber growth of 15% to more than 9.3 million.

Now what: The year marked the sixth consecutive year where MetroPCS added more than 1 million net subscribers. CEO Roger Linquist chalked up the strength to the carrier's compelling smartphone lineup and continued investment in its CDMA network. Linquist also said he expects to offer Android gadgets on its 4G LTE network at lower prices throughout the second half of the year. Since 2010, when it started including Android in its lineup, 35% of subscribers are now on smartphones.

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