Apple shares hit a new all-time high on Friday as US stocks closed out the week with a second day of solid gains that put the Dow at its highest level since the last days of 2007.

Apple shares rose to a high of $US648.19 ($A619) following reports that it was nearing the launch of a new iPhone model and a reduced-size iPad.

The stock closed up by 1.9 per cent at $US648.11.

Meanwhile, Facebook continued its fall, losing four per cent in the second day after pre-IPO investors were allowed to sell their shares. At $US19.07, the shares were almost exactly half of the May 18 initial offer price of $US38.


The Dow Jones Industrial Average finished up 25.09 points (0.19 per cent) at 13,275.20, while the broader S&P 500 added 2.65 (0.19 per cent) to 1418.16.

With the help of Apple, the world's largest company by market capitalisation, the tech-heavy Nasdaq gained 14.20 points (0.46 per cent) to 3076.59.

Trade got a little help from a rise in the University of Michigan Consumer Confidence index, which came in slightly higher than in July at 73.6, still well below pre-recession levels.

But consumers' expectations of future conditions worsened, the sub-index falling to 64.3 from 65.6.

"Clearly consumers feel times aren't as bad as they were just a month ago, but looking into the future there remains a considerable amount of uncertainty and downside risks that could undermine the recovery," said Lindsey Piegza of FTN Financial.

Caterpillar added 1.6 per cent after tentatively reaching a new contract deal with workers at its Illinois plant who had been on strike since May.

Clothing retailer Gap rose by 4.8 per cent after turning in a 20 per cent rise in second-quarter earnings and raising its forecast for the full year.

Sports shoe chain Foot Locker reported a 59 per cent rise in quarterly profit, pushing its shares 1.7 per cent higher.

American bond prices gained after falling three straight days. The 10-year US Treasury yield fell to 1.82 per cent from 1.84 per cent on Thursday, while the 30-year moved to 2.93 per cent from 2.96 per cent. Bond yields move inversely to prices.