Opening Bell: Stocks Waver on ECB Inaction; Apple Watch Sales Sink

U.S. stocks were mixed on Thursday, following the European Central Bank's decision to keep key interest rates unchanged. The central bank is waiting for more economic data to gauge the fallout from last month's landmark Brexit vote. 'It was clear that [ECB President Mario] Draghi and the ECB was going to wait for more information on the Brexit vote before deciding their next step,' said Brian Rehling, co-head of global fixed income at Wells Fargo Investment Institute. General Motors (GM) - Get Report shares rose after reporting a 157 percent increase in second quarter profit year-over-year. Net income of $1.86 a share topped estimates of $1.52. Revenue of $42.4 billion rose 11 percent year-over-year, eclipsing estimates of $38.34 billion. Apple (AAPL) - Get Report Watch sales sunk 55 percent year-over-year in second quarter, according to research firm IDC, which examined shipments. Overall smart watch shipments fell 32 percent. Apple's market share slipped, while Samsung Electronics' (SSNLF) share in the smart watch space grew. TheStreet's Scott Gamm reports from Wall Street.