It's just what companies need at this point in the dour economic cycle -- some magic fruit or potion that gives them a level of immunity from the financial malaise. Telecom giant AT&T (NYSE:T) had its "love at first bite" experience long ago and hasn't looked back: The Apple (NASDAQ:AAPL) iPhone continues to be a pillar of strength in AT&T's business.

AT&T reported a 23% drop in earnings in the final quarter of the year, but managed to eke out a 2.4% increase in revenue, up to $31.1 billion. Helping the telecom giant get there was the signing up of a net 2.1 million wireless subscribers, which included the activation of a whopping 1.9 million iPhone 3G handsets. While these customers spend an attractive 60% more each month on average, they don't come cheap -- AT&T took a loss of $450 million to subsidize the iPhone's cheap offering price.

The company also showed other strong trends, such as a near-doubling of broadband wireless accounts for laptop computers through its 3G LaptopConnect cards. With PC makers like Dell (NASDAQ:DELL), Lenovo, and Sony offering the cards integrated at purchase, more consumers are buying AT&T's services bundled with new machines.

The strong operational results and great-considering-the-economy financials have to have AT&T investors feeling a little better these days, especially considering there's a new big kid on the block. With Verizon Wireless – a joint venture of Verizon Communications (NYSE:VZ) and Vodafone -- completing its merger with Alltel recently, AT&T lost the largest-wireless-provider crown. Verizon now sits on a subscriber base of well more than 80 million, ahead of AT&T's 77 million, and it also sold a lot of Research In Motion (NASDAQ:RIMM) BlackBerry Storm handsets last quarter -- more than a million by the company's account.

While Verizon's sales of the Storm could have been better, the million that it did push out of stores certainly hasn't seemed to detract from AT&T's success. It looks like the smartphone space isn't a zero-sum game after all, as all carriers -- including Sprint Nextel (NYSE:S) and other device manufacturers like Samsung, HTC, and Nokia -- (NYSE:NOK) are privy to an expanding market. In that sense, times are still good for AT&T and its shareholders.

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Fool contributor Dave Mock categorizes eating lima beans as a kid as a near brush with death. He owns no shares of companies mentioned here. Sprint Nextel, Dell, and Nokia are Inside Value picks. Apple is a Stock Advisor recommendation. The Fool's disclosure policy makes lemonade out of lemons.