San Francisco -- Biz Stone, the co-founder of San Francisco-based microblogging giant Twitter, said he will depart the company on a day-to-day basis to reunite with former partners Evan Williams and Jason Goldman, who originally worked together at Google. The trio will relaunch Obvious, a San Francisco-based company they formed in 2005 that eventually gave birth to Twitter. "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," wrote Stone on his blog. "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." Stone said the goal of Obvious will be to develop systems that "help people work together to improve the world."