The company experienced rapid growth. It had 400,000 tweets posted per quarter in 2007. This grew to 100 million tweets posted per quarter in 2008. In February 2010, Twitter users were sending 50 million tweets per day. By March 2010, the company recorded over 70,000 registered applications. As of June 2010, about 65 million tweets were posted each day, equaling about 750 tweets sent each second, according to Twitter. As noted on Compete.com, Twitter moved up to the third-highest-ranking social networking site in January 2009 from its previous rank of twenty-second.
Twitter acquired application developer Atebits on April 11, 2010. Atebits had developed the Apple Design Award-winning Twitter client Tweetie for the Mac and iPhone. The application, now called "Twitter" and distributed free of charge, is the official Twitter client for the iPhone, iPad and Mac.
From September through October 2010, the company began rolling out "New Twitter", an entirely revamped edition of twitter.com. Changes included the ability to see pictures and videos without leaving Twitter itself by clicking on individual tweets which contain links to images and clips from a variety of supported websites including YouTube, Flickr, as well as a complete overhaul of the interface, which shifted links such as '@mentions' and 'Retweets' above the Twitter stream, while 'Messages and 'Log Out' became accessible via a black bar at the very top of twitter.com. As of November 1, 2010, the company confirmed that the "New Twitter experience" had been rolled out to all users.
On April 5, 2011, Twitter tested a new homepage, as well as phased out the "Old Twitter." However, a glitch came about after the page was launched, so the previous "retro" homepage was still in use until the issues were resolved. On April 20, 2011, the new homepage was reintroduced, though the "Switch to Old Twitter" option is still available to users.
