Stocks set to advance at the open

U.S. stocks were set for a higher open Friday morning as sentiment on the economy turned slightly more positive again following jobs data. Increasing commodity priced also helped. But expect a volatile session as is usually the case on a quadruple witching day.

The smartphone sector will be in focus today after BlackBerry maker Research In Motion (RIMM) reported results that beat Wall Street estimates but gave a disappointing outlook, and as Apple Inc.'s (AAPL) new iPhone launches today.

More here: Before the bell: Stocks poised for higher start as sentiment turns positive again