The iPhone 5s is off to an incredibly impressive start in the U.S. and especially China, where Apple was hoping to make greater inroads in 2013. Courtesy / Dave Smith

The iPhone 5s is a bona fide hit -- not that many doubted it would be -- and judging by the numbers alone, the iPhone 5s is off to a most impressive start in the U.S. and especially China, where Apple was hoping to make greater inroads in 2013.

Thanks in large part to sales of the iPhone 5s, which was released in 11 countries on Sept. 20, Apple Inc. (NASDAQ: AAPL) is now the third-largest smartphone player in China, according to Hong Kong-based market research firm Counterpoint Research. Since October, the iPhone 5s has comprised 12 percent of all smartphone sales in the country, which has caused Apple’s once-paltry smartphone market share to quadruple in China.

San Francisco-based analytics firm Mixpanel says the iPhone 5s also represents 10 percent of all iPhones now in use.

“[The iPhone 5s] definitely was more successful compared to what [the] iPhone 5 registered in terms of overall sales in a month,” Tom Kang, a Counterpoint researcher, told The Guardian.

Though the high-end iPhone 5s is responsible for the spike of Apple’s smartphone sales in China, the Cupertino, Calif.-based iPhone maker has yet to release its 2013 iPhone lineup on China Mobile, which is the largest carrier in the world with more than 740 million subscribers. The iPhone 5s is currently available on China’s other two major carriers, China Telecom and China Unicom, but China Mobile is the big cash cow, with more subscribers than all the U.S. carriers combined, including Verizon Wireless, AT&T and Sprint.

Speaking of the U.S., the iPhone 5s has been the top-selling smartphone since September at all the major carriers, including Verizon, AT&T, Sprint and T-Mobile. The next-best selling smartphone after the iPhone 5s is the Galaxy S4, and the cheaper iPhone 5c, which is similar in many ways to last year’s iPhone 5, is third.

Despite the popularity of the iPhone 5s, availability for Apple’s high-end iPhone is much improved since its initial release, when it was “grotesquely unavailable”; currently, the iPhone 5s is shipping “within 24 hours” as it nears 100 percent availability for all colors and storage capacities via Apple’s online store and physical retail stores.

Apple should extend its lead over other smartphone vendors and models with the coming release of the iPhone 5s and iPhone 5c on China Mobile, but sales on the expansive network may affect availability of iPhone supplies globally during the gift-giving season.

“[Having]Apple iPhone 5s at all three carriers will for sure ignite a price war, boosting the overall iPhone 5s sales in China,” Kang said. “This might allow Apple to even reach the No. 1 smartphone player in December or January in China.”

About The iPhone 5s

The new iPhone 5s is an impressive improvement over the iPhone 5, even though both phones have the same form factor. The iPhone 5s features the same 4-inch Retina display and chamfered diamond-cut edges, but the phone also comes with a number of new innards. The iPhone 5s is powered by a new A7 processor -- with CPU performance 40 times faster and GPU performance 56 times faster than the original iPhone -- and Open GL, just like the new Nexus 7. To supplement the A7 chip, the release of the iPhone 5s also comes with Apple's new M7 chip, which contains all the motion-tracking hardware Apple needs to make its iWatch a reality. By packing so many components into the M7 motion co-processor, including an accelerometer, gyroscope and compass, the M7 can continuously measure motion data for the newest generation of health and fitness apps.

The iPhone 5s also features a slightly modified battery for greater life, a new and improved camera system packed with new features and technologies that make for better quality images and videos, and a fingerprint sensor called Touch ID, which lets users authenticate ownership and user passwords by simply holding their thumbs on the iPhone’s signature home button. Apple chose to release the iPhone 5s in three color options -- white with silver, white with gold and black with space gray -- but for more information on the new iPhone 5s, check out our review and hands-on with the seventh-generation iPhone, and learn more about why it's worth the price to upgrade.

What do you think of the iPhone 5s? Would you purchase the iPhone 5s over the iPhone 5c, despite the $100 price difference? Are you impressed by the features in the iPhone 5s, or do you prefer another smartphone out there? Let us know your thoughts in the comments section below.

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