US stocks turned lower in early trade Monday, while Apple scored gains on record launch sales for its new iPhone models.
After opening flat, the Dow Jones Industrial Average was down 18.04 points (0.12 percent) at 15,433.05 after a half hour of trade (1400 GMT).
The broad-market S&P 500 index fell 6.25 (0.37 percent) to 1,703.66, while the Nasdaq Composite lost 4.84 (0.13 percent) at 3,769.89.
Apple jumped 4.4 percent to $488.00 after saying it sold more than nine million new versions of its iPhones over the three-day launch weekend, a record. Apple predicted its fourth-quarter profit and revenue would be at the high end of its prior forecast.
Microsoft was unchanged. The US tech giant will hold a media launch of its new version of the Surface tablet later in the morning.
BlackBerry meanwhile tumbled 2.7 percent to $8.49, extending a 17 percent dive Friday after forecasting up to a $1 billion loss in its second quarter.
"In 2013 and probably onwards competitive position of Apple is extremely good," said Trip Chowdhry of Global Equities Research.
"BlackBerry is dead... Windows Surface and Phone is dead... Nokia is on life support," he said.
"Demand for Apple products today is much stronger than ever."
It was the first day of trading of the newly configured Dow index of 30 blue-chip stocks, with Goldman Sachs, Nike and Visa replacing Alcoa, Bank of America and Hewlett-Packard.
Dow member General Electric gained 1.2 percent after winning a $2.2 billion contract to provide turbines for six power plants in Algeria.
Global markets were mixed. European markets drifted higher after German Chancellor Angela Merkel won a landslide reelection Sunday. Asian markets were mixed after better-than-expected Chinese manufacturing data.
Bond prices rose slightly. The yield on the 10-year Treasury slipped to 2.72 from 2.73 percent Friday, while the 30-year edged down to 3.75 from 3.76 percent. Prices and yields move inversely.