Twitter co-founder is moving on

Isaac “Biz” Stone is moving on from Twitter, just five years after co-founding the microblogging site that has become integral to the social media scene around the globe.

Stone, 37, said on his blog that he will work with the company “for many years to come,” but that the most effective use of his time now is to “get out of the way” of Twitter’s crew and leadership team until he’s called upon to be of some specific use.

Stone says he plans to focus on helping schools, nonprofits and company advisory boards. He’s also relaunching Obvious Corp. with fellow Twitter co-founder Evan Williams to develop new projects.

The move comes as Twitter has been trying to build upon its popularity to make more money by selling more ads. The privately held company doesn’t disclose its finances, but research firm eMarketer Inc. estimates Twitter will bring in advertising revenue of about $150 million this year.

Stone’s departure caps a year of executive changes at the San Francisco-based company. Last fall, Williams handed over the reins to Twitter’s current CEO, Dick Costolo, and moved on to explore new business ideas. In March, Twitter’s third co-founder and original CEO Jack Dorsey returned to oversee product development as executive chairman.

Microsoft launches Web-based Office

Microsoft Corp. has officially launched its Web-based email and Office services, part of its ongoing effort to keep Google at bay when it comes to business software.

“Office 365” has been available in a test version since last year. It combines Web-based versions of Word, Excel and other Office applications. It also includes the Exchange email system, SharePoint online collaboration technology and Microsoft’s instant messaging, Internet phone and video conferencing system.

The latest software package comes as companies are increasingly shifting to storing data and applications on remote servers rather than on users’ desktop computers. In 2006, Google Inc. launched its own suite of office software that’s based in the “cloud,” called Google Apps.

Microsoft said last week that it plans to charge $2 to $27 per month per user for Office 365 depending on what’s included. Google Apps costs $4 or $5 per month. 

E-reader ownership growing fast

A study finds that 12 percent of U.S. households now own a reading device for electronic books, such as Amazon’s Kindle.

That’s three times the number of households that owned an e-reader just a year ago, pointing to rapid acceptance.

The phone survey published Monday was conducted in April and May by the Pew Internet and American Life Project.

Prices for e-readers have fallen rapidly over the past year. Barnes & Noble’s Nook is growing as a competitor to the Kindle. The cheapest models are now available for just above $100.

The survey also found that ownership of tablet computers such as the iPad has doubled over the past year to 8 percent of households.

The survey had a margin of error of plus or minus 2 percentage points.

Pew also asked households if they had a desktop or laptop computer, a question it has posed since 2006. Desktop households have outnumbered laptops until this year. For the first time, the two figures were within the margin of error, at 57 percent and 56 percent respectively — a statistical dead heat. Laptop ownership has nearly doubled since 2006, while desktops have declined slightly.