SAN JOSE (CBS SF) — Silicon Valley stalwarts — Apple, Facebook and Google — all suffered significant losses during Friday’s 666-point Dow sell-off.

Apple’s stock fell more than 4% on Friday — a day after the company released strong earnings results, but failed to fully dispel lingering concerns about iPhone demand.

Meanwhile, shares of Google parent Alphabet slumped 5% even after the tech behemoth posted its first $100 billion sales year and Facebook saw a 1.46 percent dip, losing $2.81 a share.

Among the few tech winners on the day were Amazon and Netflix. Amazon continued its impressive surge with shares jumping 2.87 percent or nearly $40 a share to $1,429 while Netflix ended the day up 0.89 percent or $2.36 a share to finish at $267.43.

While those stocks were up, most of the talk during the day focused on Apple and its drop.

“From our perspective, the quarter was a mixed bag,” Sherri Scribner, an analyst with Duetsche Bank, wrote in an investor note after Apple earnings results were released Thursday.

Apple’s decline, which came amid a broader market sell-off, pushed the company into correction territory. That means the stock was down more than 10% from its most recent high, which was reached last month.

Apple posted record sales of $88 billion for the final three months of 2017 fueled in part by the higher price tag of the iPhone X, which went on sale during the quarter.

However, the total number of iPhones sold during the quarter declined 1% from the same period a year earlier. Worse still: Apple expects sales for the upcoming quarter to be between $60 billion and $62 billion, well below Wall Street estimates.

The weaker sales forecast and slight dip in iPhones sold fuel lingering investor concerns about demand for Apple’s current iPhone lineup, including the $999 iPhone X model and the more affordable iPhone 8 and 8 Plus.

“From our perspective, the quarter was a mixed bag,” Sherri Scribner, an analyst with Duetsche Bank, wrote in an investor note after the earnings results were released Thursday.

\The questionable iPhone demand was offset to some extent by a surge in the average price of each iPhone sold, as well as Apple’s plans to return cash to shareholders as a result of the tax bill signed into law late last year.

“The quarter had enough of both positives and negatives to keep the bulls and bears firmly in their own camps for now,” Scribner wrote.

Daniel Ives, an analyst with GBH Insights, now expects Apple to ship between 235 million to 240 million iPhones in the 2018 fiscal year, down from 255 million previously. But Ives says the higher price tags, tax repatriation and product launches later in the year could help make up for that.

“This is a hand holding period starting with tonight’s call,” Ives wrote in an investor note Thursday night. “We believe near term turbulence does not change our long term bullish thesis on Apple.”

The stock slipped in the days before the earnings release as multiple news outlets reported Apple was cutting production for the iPhone X by half for the first three months of 2018.

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