2012 wasn't exactly the transformative year AT&T (T 1.88%) had hoped it would be. The telecom giant pursued a $39 billion merger with smaller rival T-Mobile USA to the bitter end, but the game-changing deal was nixed by regulators at the tail end of 2011. Ma Bell paid a $4 billion breakup fee, including a portfolio of spectrum licenses, and moved on.

My oh my, how different the year could have been with T-Mobile's assets under the belt. But AT&T didn't exactly suffer anyhow:

T Total Return Price Chart

T Total Return Price data by YCharts.

The stock edged out its Dow Jones Industrial Average (^DJI -0.11%) peers any way you slice it, and it dominated the leading market index if you reinvested AT&T's generous dividends along the way.

Notably, the stock zigged upward over the summer, while the Dow zagged downward. Notably, both AT&T and fellow megatelecom Verizon (VZ -0.53%) reported outstanding quarterly results in April. The leading telecoms sent strong signals that iPhone sales aren't as important as they used to be. They'd be happy to stop sending massive subsidy checks to Cupertino, and they might go down that road someday soon. The afterglow from these reports lasted all summer long, even as they damaged the share price of iPhone maker Apple (AAPL 1.27%).

The mobile industry is evolving at breakneck pace right now. High-profile mergers are happening everywhere, the radio spectrum crunch is just as real as the fiscal cliff, and smartphones have matured into a de facto replacement for basic feature phones. AT&T is adjusting to all these changes like a champ so far.