Aided by a growth in mobile app usage, Twitter has topped 145 million users, up from 105 million in April.
Twitter co-founder Evan Williams made the announcement in a blog post about the micro-blogging service's "evolving eco-system" – one that is increasingly reliant on the mobile space.
Total mobile usage has jumped 62 percent since mid-April, and 16 percent of all Twitter users start using the service on a mobile phone, Williams said.
In April, Twitter acquired iPhone client Tweetie from Atebits. The company turned Tweetie into an official Twitter app, renamed it Twitter for iPhone and iPod touch, and launched it in the App Store in May.
"As we had hoped in April, these clients are bringing more people into Twitter, and, even better, they are attracting and retaining active users," Williams said. "Indeed, 46 percent of active users make mobile a regular part of their Twitter experience."
Williams posted a chart of the top 10 applications Twitter users have used to access the service in the last 30 days. Totals do not equal 100 percent because some people used more than one app, but about 78 percent of people have logged in via Twitter.com and another 14 percent have checked their feed via the mobile site, m.twitter.com, he said.
About 8 percent access Twitter via text messages.
Twitter for iPhone and BlackBerry are two of the more popular ways to access the service, Williams said, attracting 8 percent and 7 percent of users in the last month, respectively. Another 4 percent have accessed TwitPic, and 3 percent have used Tweetdeck as well as Echofan. About 2 percent have also signed on via Google Friend Connect and UberTwitter.
TweetDeck users, Williams said, are "some of the most active and frequent."
"As this data shows, while smartphone clients are important, there are even more people who use the mobile Twitter Web site and/or SMS," Williams said. "We've been seeing strong growth in both of these areas."
And while there is a dip in percentages between Twitter.com and some of the more popular third-party apps, they are competing with a "tremendous" number of apps. "The number of registered OAuth applications is now at almost 300,000—this number has nearly tripled since Chirp," Williams said, referring to the company's developer conference.