Twitter co-founder Biz Stone steps away

Twitter co-founder Biz Stone is stepping away from his day-to-day duties at Twitter.

Stone announced yesterday that he is “getting out of the way” at the microblogging site and making better use of his time by teaming up with another Twitter co-founder, Evan Williams, and former Twitter product chief Jason Goldman to restart the Obvious Corp., which helped to kick start Twitter.

The Obvious Corp. will focus on developing new projects.

Stone added that he will continue to work part time at Twitter, but will also focus part of his time on company advisory boards, as well as working on The Biz and Livia Stone Foundation, an institution set up with his wife that supports education, wildlife and conservation programs.

“My work on Twitter has spanned more than half a decade and I will continue to work with the company for many years to come,” Stone wrote. “During this time, especially lately, it has come to my attention that the Twitter crew and its leadership team have grown incredibly productive. I’ve decided that the most effective use of my time is to get out of the way until I’m called upon to be of some specific use.”

Twitter CEO Dick Costolo will remain at Twitter’s helm.

This isn’t the first management switch at Twitter. In October, Williams stepped down as the company’s CEO, making room for Costolo, who had been Twitter’s chief operating officer. Williams was reportedly focusing his efforts on “product strategy.”

With Costolo — who is known as a tech entrepreneur and overall business strategist – in charge, the company recently acquired TweetDeck . The move successfully undermined a deal that Twitter-rival UberMedia was working on to snare TweetDeck.

In May, Twitter Chief Technology Officer Greg Pass also left the company . Twitter gave no reason for Pass’ departure and said the company did not plan to fill the position.