Twitter revenue grows sharply, but user growth stays low

Twitter has failed to add users at a quick enough pace for investors in the second quarter, even as revenue grew sharply, feeding concerns about whether it can ever become a mass-market service like Facebook or Google.

The beleaguered company is searching for a permanent chief executive to replace Dick Costolo, who stepped down at the beginning of this month. Co-founder and chairman Jack Dorsey is serving as interim CEO.