After first knocking Google (Nasdaq: GOOG) and its Android operating system from the top spot in the U.S. smartphone market for the fourth quarter of 2011, and then completely crushing fourth-quarter earnings expectations, Apple (Nasdaq: AAPL) has reached yet another important milestone.

We're No.  3!
By selling 37 million iPhones in 2011's fourth quarter, Apple solidly cemented its position as the No. 3 cell-phone manufacturer in the world. As it now stands, the company holds 8.7% of total global market share. In 2010's fourth quarter, Apple held only a 4% global market share, a staggering jump considering the size of the worldwide market -- 1.5 billion phones sold in 2011.

The No. 1 mobile-phone manufacturer in the world is still Nokia (NYSE: NOK). The company sold 113 million handsets in Q4, an 8.2% decline for the embattled mobile-phone giant, leaving it with a global market share of 30.7%. That figure sounds good, but the vast majority of the sales were feature phones, low-margin products the company needs to move away from.

To that end, the company has just launched its Lumia line of smartphones, developed in cooperation with Microsoft and running the tech stalwart's Windows Phone operating system. Nokia has reported selling more than 1 million Lumias so far, but that's still not enough to make a real impact on global market-share percentages yet.

Samsung remains the world's second-largest mobile-phone manufacturer. The company sold 97 million mobile phones in Q4, giving it a global market share of 20%. Apple had previously been the fifth-largest mobile-phone manufacturer in the world, behind LG and ZTE. IDC, the research firm responsible for compiling and reporting these numbers, attributes the two-position jump mainly to the incredible success of the iPhone 4S.

The little company from Cupertino that could
Apple's iOS also recently surpassed Google's Android as the most popular smartphone operating system in the U.S., an incredible testament to the brand's strength. Achieving the rank of third-largest mobile-phone manufacturer in the world shows that brand strength is on the rise.

In comparison, Google's Android platform is easily adapted by most any handset manufacturer. While that's good for Google, it's not necessarily good for handset makers, whose Android-driven products become commodities competing with the many other Android handsets out there. Your Foolish columnist has yet to see offers for free iPhones, but there have been more than a few offers for free Android OS phones. Yet Apple has climbed from the fifth-largest mobile-phone manufacturer in the world to No. 3 in the space of a single year. Brilliant. What's next, then?

All Hail the iPhone 5
In 2012, Apple and its investors have the iPhone 5 to look forward to, rumored to be launched sometime in the summer or maybe fall. Last summer, Apple initially seemed to disappoint both investors and iPhone aficionados by introducing an iPhone 4 revamp, the iPhone 4S, rather than the hoped-for iPhone 5. Yet the iPhone 4S sold in record numbers, boding very well for what the iPhone 5 might do.

But even with Apple's astonishing earnings report and this worldwide milestone reached, the stock is trading with a P/E of 13. Why so low? Do investors think the company has been on too strong of a run for too long? Maybe they do, but maybe then they need some help seeing the glass half-full. That is, after steadily clawing its way back from the brink of bankruptcy year after year since the late '90s, Apple probably deserves the benefit of the doubt at this point. As such, with its P/E of 13, now might be the perfect time to get in on a great company that seemingly can't help but do great things.

3 hidden winners of the smartphone revolution
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