Smartphones had an explosive year in 2012. According to IDC, 219.4 million smartphones were shipped in the fourth quarter, rising 36.4% since the fourth quarter of 2011. Smartphones made up 45.5% of all mobile phone shipments, the highest ever. For the full year, 712.6 million smartphones were shipped in 2012, an increase of 44.1% since 2011. Google Inc (NASDAQ:GOOG)'s Android OS has benefited tremendously from this explosive growth. Its mobile operating system commanded an astounding 75% market share in the third quarter of 2012. Judging by its most recent earnings announcement, there's no indication that Google Inc (NASDAQ:GOOG)'s momentum has begun to slow. Is it safe to say that Google Inc (NASDAQ:GOOG) has officially won the smartphone war?

Not your average fruit? Apple Inc. (NASDAQ:AAPL) shipped 47.8 million iPhones in the fourth quarter, which represented a 29.2% year-over-year increase. Although Apple's total numbers are impressive, its year-over-year growth rate has something left to be desired. That's because it's actually far below IDC's fourth-quarter industry growth rate of 36.4%. The fact that Apple grew substantially slower than the overall smartphone market does not bode well for shareholders. In this context, I don't find it surprising that Apple shares were punished after it released its first-quarter earnings results last week.

Samsung, on the other hand, which happens to be the leading Android device manufacturer, grew its year-over-year shipment volume by 76%, handily beating out Apple for the No. 1 smartphone manufacturer spot with 63.7 million units shipped. As a whole, the industry is incredibly slanted toward Android OS, given that fact that four out of the top five smartphone manufacturers in the world utilize Android. Together, these four manufacturers accounted for over 42% of all smartphones shipped in the fourth quarter, which all experienced faster year-over-year growth than the industry. In other words, the Android ecosystem is seen growing faster than the smartphone industry, while Apple is growing slower than the industry. This simple understanding helps justify why Apple's P/E is deeply discounted relative to both Google Inc (NASDAQ:GOOG) and the general market.

Tablet wars IDC estimated that 122.3 million tablets shipped in 2012, driven by robust demand for both Android and iOS devices. Apple's iOS commanded the lion's share with 53.8% of the market, Android came in second place with 42.7% of the market, and Microsoft Corporation (NASDAQ:MSFT) came in third with 2.9% of the market. By 2016, Apple is expected to hold onto 49.7% of the market, Android 39.7%, and Microsoft 10.3%. IDC expects that more than 282 million tablets will ship in 2016.