Two of Twitter's founders are back in the start-up game.
Evan Williams and Biz Stone left Twitter earlier this year, and in June announced that they were joining forces with Jason Goldman, Twitter's former product chief, to work on a secretive new company called the Obvious Corporation. The idea, they said, was to create a start-up lab to build products.
Mr. Stone announced the first of those products on Tuesday -- Lift, an app for achieving goals through positive reinforcement. He did not say much more about Lift, but interested users can sign up on its Web site to learn more once the app is available to the public.
Mr. Williams and Mr. Stone have talked frequently about using technology to improve the world, and in a blog post, Mr. Stone said that Lift fits that mold.
"People are responsible for change -- technology just helps out," Mr. Stone wrote. "At Obvious, our goal is to foster systems that help people work together to improve the world."
He also revealed more about how Obvious will work. Like other start-up labs that successful entrepreneurs have recently founded, including Firespotter Labs and Milk, Obvious will be a place where new start-ups can get off the ground.
That will happen in three ways, Mr. Stone wrote. Obvious will build its own apps, invest in others and form partnerships with start-ups. With Lift, Obvious will help with design, strategy, recruiting and fund-raising. It also invested in the start-up, which was started by Jon Crosby and Tony Stubblebine, who worked with Mr. Williams and Mr. Stone at Odeo, the start-up that spun off Twitter. They are calling Lift "an Obvious company."
"We offer our team's combined expertise while Lift maintains the freedoms of a new start-up," Mr. Stone wrote.