Sales of the Apple iPhone may have missed Wall Street's lofty expectations, but the smartphone's future remains extremely bright.
That's the message CEO Tim Cook wanted to offer Tuesday evening after his company, revealing iPhone sales of 47.5 million, below analysts' estimates by about 2 million phones.
"We think the phone has a lot of legs to it," Cook said on a call with analysts Tuesday. "Many, many, many years. There's ton of innovation left in the phone. I think we're in the early innings of it, not in the late innings."
Cook was quick to defend his marquee product because of the outsize impact it has on Apple. Investors will react to any sales figures involving the iPhone, since it's now the primary moneymaker for Apple, the highest-valued company in the world. In the latest quarter, iPhone sales were $31.4 billion, accounting for 63 percent of the Cupertino, California, company's total revenue. Since Apple's success is now tied so closely to the iPhone, Cook spent plenty of time tamping down concerns that the product is anything but a huge blockbuster -- as it's often proved to be in past quarters.
Nevertheless, Apple's lighter-than-expected iPhone sales -- albeit during what's typically its weakest quarter -- spooked Wall Street, with investors driving down the company's shares by 6.4 percent after hours. Prior to the market close, the stock was up 18 percent so far this year.
"We did exceptionally well in any way that you look at it," Cook said on the call. "From our point of view the iPhone is doing outstanding."
Cook bolstered his claims by saying iPhone unit sales -- despite coming in below Wall Street estimates -- were up 35 percent from a year ago, easily outpacing broader smartphone sales, with strong growth in Western Europe, South Korea and Greater China.
He added that only 27 percent of iPhone users have upgraded to the latest model -- the iPhone 6 or 6 Plus -- which is a "very bullish sign...that there is a lot of headroom left for upgraders."
Additionally, he said, during the latest quarter Apple saw its highest rate of people switching to the iPhone from phones powered by Google's Android operating system. Apple's move to a larger display on the iPhone 6 and 6 Plus has proved successful in winning over Android users who preferred a bigger-screen device.
For the current quarter, Cook said the company is predicting another strong period for the iPhone.
"We're very confident that this quarter's going to be great," he said. "How the future looks, we'll take it one quarter at a time."