For Apple, today is part good news, part bad news. While the tech giant reported better-than-expected earnings on an increase in revenues, and record sales of iPhones during its fiscal fourth quarter, investors apparently aren't all impressed.

For the three-month period ended September 28, Apple reported $37.5 billion in revenue, topping the $36.8 billion analysts had expected and marking a 4 percent increase from the same period last year.

From those revenues, Apple earned a net profit of $7.5 billion, or $8.26 a share, down from $8.2 billion, or $8.67 a share, a year ago. Analysts had expected earnings of $7.93 a share.

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The quarter also set a record for iPhone sales, which Apple says reached 33.8 million. That's compared to 26.9 million in the year-ago period. In September, Apple released its updated iPhone 5S and 5C models.

Sales of the iPad remained flat during the quarter at about 14 million sold, the company said.

For the 12-month period, Apple reported net sales of $170.9 billion, up from $156.5 billion in fiscal 2012. Profits were down for the year as well as the quarter, with Apple racking in $37 billion in net income compared to $41.7 billion last year.

Despite "a strong finish to an amazing year," as Apple Chief Executive Tim Cook said in a release, investors didn't seem as pleased with the results. Apple stock was down about 3 percent in after hours trading.

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