Futures for the S&P 500 were down 0.07 percent, Dow Jones futures were 0.14 percent lower while Nasdaq 100 futures were up 0.12 percent at 0904 GMT.

European shares were mostly unchanged, halting a three-day tentative recovery rally following a two-notch downgrade of Spain's credit rating ahead of a key Italian bond auction.

On the macro front, investors awaited the first estimate of U.S. first-quarter gross domestic product (GDP), due at 1230 GMT. The figures are expected to show the economy expanded at a 2.5 percent annual rate, a Reuters poll found. That would be a moderation from the fourth quarter's 3.0 percent expansion but decidedly stronger than economists' predictions early in the quarter for growth below the 1.5 percent level.

Institutional investors pulled back from equity funds in the week to April 25, resulting in a modest net outflow for the sector overall, Thomson Reuters' Lipper service data showed on Thursday.

Amazon.com Inc's (AMZN.O) quarterly results beat Wall Street's most bullish expectations as heavy spending by the world's largest Internet retailer began to pay off through sales of more digital products on its new Kindle Fire tablet.

Starbucks Corp (SBUX.O) reported better-than-expected quarterly profit but global sales at established coffee shops fell short of analysts' estimates due to weakness in Europe, sending its shares down 5 percent in after-hours trade on Thursday.

Newmont Mining Corp (NEM.N), the world's second-largest gold producer, said its quarterly profit rose as gold prices outpaced higher labor and power costs at its mines.

Top U.S. weapons maker Lockheed Martin Corp (LMT.N) posted a higher-than-expected first-quarter net profit and announced a succession plan that will bring in President Chris Kubasik as chief executive officer in January.

Gilead Sciences Inc's (GILD.O) reported quarterly earnings that fell slightly short of Wall Street estimates as sales of its flagship HIV drugs rose nearly 20 percent but expenses also moved higher.

Ally Financial Inc, the U.S. government-owned lender, said its mortgage unit could file for bankruptcy, in the company's most direct statement so far about its plans for the struggling business.

Samsung Electronics (005930.KS) posted a record $5.2 billion quarterly profit as it shifted over 20,000 Galaxy smartphones an hour in January-March, outselling Apple's (AAPL.O) iPhone in a duel for the lucrative high end of the mobile industry.

Online travel agency Expedia Inc (EXPE.O) topped estimates for quarterly profit growth as its worldwide hotel revenue increased, and its shares gained 16.5 percent.

U.S. health regulators rejected the application by Amgen Inc (AMGN.O), the world's biggest biotechnology company, to expand the use of the drug Xgeva to delay the spread of tumors to the bone in patients suffering from advanced prostate cancer.

Shares in Foxconn International Holdings Ltd (2038.HK), whose parent Foxconn Technology Group helps assemble Apple Inc's (AAPL.O) iPhones and iPads, fell 13 percent on Friday to a six-month low after the world's biggest contract maker of cellphones warned that weaker demand from some key customers would widen first half losses.

U.S. stocks rose for a third day on Thursday after upbeat housing data and stronger-than-expected results from companies, including Citrix Systems Inc (CTXS.O), overshadowed some high-profile earnings misses.

The Dow Jones industrial average .DJI rose 113.90 points, or 0.87 percent, to close at 13,204.62. The Standard & Poor's 500 Index .SPX advanced 9.29 points, or 0.67 percent, to 1,399.98. The Nasdaq Composite Index .IXIC gained 20.98 points, or 0.69 percent, to 3,050.61.

(Reporting by Blaise Robinson)

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