Apple has a tough job come earnings season. For the past few years it has consistently been one of the world's most valuable and profitable companies, recently setting the record for the largest quarterly profit in history. The downside of that success, if you're the glass half empty type, is that investors are prone to knock down its share price when it fails to deliver stellar results that continue that upward momentum. That explains today: while Apple reported strong earnings, it was a touch below expectations on devices sold, driving the stock down slightly in after hours trading.

The company made $51.5 billion in revenue and $11.1 billion in profit, or $1.96 per share. That beat with analysts' predictions of $51.12 in revenue and $1.88 per share in profit. For this same period last year Apple reported revenue of $42.12 billion and earnings of $1.42 per share. For the first three quarters of fiscal 2015, the company delivered double-digit growth in both profit and revenue by unlocking the pent up demand for larger iPhones. Profit this quarter was up 31 percent year over year and revneue was up 22 percent, which Tim Cook called its strongest "absolute revenue growth ever."

This quarter's results include just a small sliver of iPhone 6S sales, although that opening weekend clocked in at 13 million units sold. Earnings for this category will still be largely driven by earlier generations of the flagship phone, and more importantly, how well that device is selling in Greater China, which is far and away Apple's fastest growing market, with sales growth of over 100 percent during the last few quarters. Mobile carriers in China have been upgrading networks for high-speed data and Apple has been opening dozens of stores around the region. This quarter the region saw growth of 99 percent, 10 times the growth rates in the Americas and nearly five times the growth rate in the rest of Asia.

In case you have any doubt about China’s importance to Apple’s growth… pic.twitter.com/nSMkUSYYwd — Jan Dawson (@jandawson) October 27, 2015

Another bright spot for Apple was Mac sales. Despite the decline in the larger PC market, the companies line of laptops has surged. It sold 5.71 million Macs this quarter, a new record. Services revenue was up 10 percent to just over $5 billion. iPhone sales rose 36 percent year over year to 48 million units. iPad sales declined again, to 9.9 million units, a drop of 20 percent year over year.

The last big data point investors are watching closely is sales of the Apple Watch. We learned last quarter that this is already a billion dollar business for Apple, making it far and away the most successful brand of smartwatch. Analysts predict that Apple was able to better meet demand this quarter, and the device became more widely accessible, going on sale in big box outlets like Best Buy and Target. Revenue for "other products", which includes the watch, was up 61 percent year over year to $3 billion, but beyond that Apple offered no detail on the performance of it's latest flagship gadget.