Apple Inc. (AAPL) is now the world's biggest watchmaker. According to estimates by research firm Asymco, Apple has sold approximately 15 million watches in the past 12 months at an average price of $330. That puts the company's total revenue from its watches at $4.9 billion. In comparison, Swiss watch company Rolex SA, which held the number one position in 2016, sold 1 million watches last year and had revenues of $4.7 billion.

To be sure, this is not the first time that the Cupertino, California-based company has been proclaimed the number one watchmaker. Apple's CEO made a similar assertion while announcing  a slate of new products, including a new version of the Apple Watch, at a company event last month. On an overall basis, Asymco estimates that Apple has sold 33 million units of the Apple Watch, generating $12 billion in revenue. Sales of the device were up by 50% during the June quarter in comparison with the prior period. The device's latest edition – the Apple Watch Series 3 – comes with a built-in cellular connection and has mostly received positive reviews from critics and experts. (See also: Apple Watch 3 Connectivity Issues Confirmed.)

Apple has primarily positioned the watch as a healthcare device and pumped money into research to prove its benefits. But the new watch also extends the company's services platform by enabling users to perform a wide variety of actions. For example, users of the Apple Watch Series 3 can receive phone calls, play music or message their contacts.

In addition to extending Apple's reach into customer lives and reducing its dependence on the iPhone, the device could translate into more revenue for services such as Apple Music. In a post explaining the watch's importance to Apple's bottom line, Asymco founder Horace Dediu writes that "the watch is effectively stealing usage" from the iPhone and could surpass the iconic device's utility by "pulling in a new direction all of its own."  (See also: How Apple Watch Threatens AT&T, Verizon.)

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