Twitter cofounder Jack Dorsey will take on a more active role at the fast-growing social networking and microblogging service, the company announced Monday.
Dorsey, who has been Twitter's nonexecutive chairman, was named executive chairman in charge of leading the company's product development.
Twitter Chief Executive Dick Costolo announced the new position for Dorsey in a tweet Monday morning, writing that he was "excited" that Dorsey was "returning to the company day-to-day leading product as Executive Chairman."
Dorsey followed up with his own tweet, saying, "Today I'm thrilled to get back to work at Twitter." He also noted that he would continue to be chief executive of Square, the mobile payment system he cofounded last May after relinquishing many of his Twitter duties.
Square is a mobile payment company that helps retailers charge for goods using smartphones and tablet computers instead of cash registers and other traditional credit and debit card readers.
Twitter spokeswoman Carolyn Penner said Dorsey's move was an example of how Twitter's three cofounders — Evan Williams, Biz Stone and Dorsey — stepped into new roles as needed.
"The timing is fortuitous," Penner said. "Not only is Twitter experiencing record growth, but we also now have a new infrastructure that will keep us ahead of that growth and enable us to launch products that will make Twitter more instant, simple and always present."