Twitter tops 145 million registered users: CEO

Williams, in a post on the Twitter blog late Thursday, also said that nearly 300,000 third-party applications have been developed around the service, which allows users to pepper one another with messages of 140 characters or less.

"These new services help people get the most out of Twitter, contributing to user growth and new business opportunities -- both of which are critical to the long-term viability of the ecosystem," Williams said.

The Twitter chief executive said the number of people using Twitter on mobile devices had jumped 62 percent since mid-April and 16 percent of new users start on mobile, up from five percent in April.

Forty-six percent of active Twitter users regularly use a mobile device, he said.

Twitter acquired a third-party mobile application called Tweetie in April and turned it into the official Twitter program for Apple's iPhone.

Applications also exist for using Twitter on Research in Motion's Blackberry and devices powered by Google's Android mobile operating system.

Williams also published figures on the top 10 applications people have used to access Twitter during the past 30 days.

Seventy-eight percent used the official Twitter.com website, 14 percent used Twitter's mobile website m.twitter.com, eight percent used SMS, eight percent used Twitter for iPhone and seven percent used Twitter for Blackberry.

Other applications in the top 10 were TwitPic, a program for uploading photos, TweetDeck, Echofon, Google Friend Connect and UberTwitter.

Twitter said the numbers add up to more than 100 percent because people often use more than one application to access the service.

(c) 2010 AFP