5 game-changers: Recent smartphone debuts that stood apart (photos)

Touch-screen smartphones may be a dime a dozen these days, but let's not get too blase about the game-changers of late who helped revolutionize a (relatively) new product category that's changed the way hundreds of millions of people consume technology each day.

When Steve Jobs pulled the iPhone out of his pocket at a the Macworld conference on January 9, 2007 -- it went on sale six months later -- Apple transformed the the mobile world. Unlike other smartphone collaborations between manufacturers and carriers, Apple got its way by insisting that only its engineers would develop the unit's hardware and software. It paid off. Even though the product was baptized in hype -- some dubbed it "the Jesus phone" -- it lived up the advance billing. Apple would go on to sell more than 73 million iPhones by the end of its fiscal 2010 year. Since then, Apple has released four newer generations of the iPhone, each one offering more and better functionality than its predecessor.

When it debuted in November 2009, the Motorola Droid stirred a frenzy among technophiles, with some suggesting it had the makings of a formidable rival to Apple's iPhone. Its debut was accompanied by rave reviews. Walt Mossberg called it "a powerful hand-held computer that happens to make phone calls" as well as "a platform for numerous third-party programs." Time chimed in with a similar high five for the Droid, dubbing it "the best Android device currently available" and "a close second to the iPhone in terms of a seamless user experience."

No doubt part of the buzz stemmed from the fact that it was the first phone to run Android 2.0. Also, the Droid benefited from features that were still lacking in the iPhone. For instance, the marketing launch made sport of the fact that while the iPhone didn't 't multitask, "Droid Does."

Perhaps more than any other smartphone of its era, the Nexus One put Google Android on the map. The Nexus One, announced in January 2010, was built to Google's specifications -- inside designed by Google and an outside designed by HTC -- and it quickly earned plaudits for its loaded feature set. In particular, the unit came with a gorgeous display and a super-fast processor. It also was the first Android handset to offer noise cancellation, with a couple of microphones that adjusted the volume level according to the background noise. Even though it didn't undercut the arguments for buying an iPhone, the Nexus One still constituted a big enhancement to the Google Android family. (And, let us recall, it also came unlocked.)

The Galaxy S II came equipped with a spectacular display, a fast dual-core chip, a 10 percent larger battery, 4G support, and a rear-facing 8-megapixel camera with 1080p HD video capture, earning kudos from CNET as "Samsung's most advanced and successful smartphone to date." When the world got its first peek at the unit at the Mobile World Congress on February 13, 2011, the Galaxy SII also drew attention for being one of the thinnest smartphones to ever come down the pike.

The HTC Evo 4G made waves in May 2010 as the first 4G smartphone available in the U.S. Though Sprint's 4G WiMax network was limited at the time, it gave everyone a taste of faster data speeds on your smartphone and put pressure on the competition to follow suit. Aside from 4G, the Evo also stood out with its spacious 4.3-inch display, a built-in kickstand, HDMI port, and video calling.