In November 2009, Twitter added user lists to its interface. In January 2010, it added location-aware tweets and local trends. In March 2010, it introduced @anywhere, a service that allows sites to embed Twitter features without requiring users to visit Twitter’s homepage. And in September 2010, it fully redesigned its web client interface, integrating @mentions, retweets, searches, and lists just above users’ timelines in a revamp that quickly became known as #newtwitter. In December 2012, it added photo filters in an attempt to compete with the photo-sharing service Instagram.

In January 2013, Twitter launched Vine, an app that allows users to share six-second looping video clips within Twitter. The service was initially seen by some as a successor to the animated GIF, and as a potential quick, simple video-sharing tool for news with a potentially major social impact.

It also sends a weekly email digest of tweets to users. The company bought the short-form blogging company Posterous in March 2012.

Twitter blocked a user account at the request of government authorities for the first time in 2012, when it banned a German neo-Nazi group’s account.

Twitter acknowledged in February 2012 that it stores the address books of the users of the “Find my friends” feature on its smartphone app, without names, on its servers for 18 months.

Twitter and journalism

Twitter has been found to be more like a news media system than other online social networks, largely because it is based on non-reciprocal relationships that often give rise to large-scale news distributors within the network. Due to its ubiquity and its integration into the everyday lives of its users, Twitter has also been described as a system of “ambient journalism.”

Many Twitter users use the network as a customized news feed, aggregating links from other users on a particular topic of interest. Nearly half of the news shared on Twitter is related to technology, one study found, and about 40 percent of the links on the service come from web-only news sources. Additionally, per another study, 72 percent of the most influential Twitter accounts are run by traditional news organizations.

According to a 2010 survey, 48 percent of journalists have accounts on Twitter or other microblogging sites. Every one of the 100 largest newspapers in the U.S. had a Twitter account by 2009, though some research has shown that they tend to use it predominantly to promote their own content.

Twitter has been a particularly effective tool for distributing breaking news, both by news organizations and citizens. The first major use of Twitter for breaking news came during the California wildfires of October 2007. Some news organizations have created separate Twitter accounts dedicated to major news events and have lists of other accounts that tweet exclusively about those events. In 2013, Twitter added human-powered filtering to its efforts to contextualize breaking news search.

Journalists have also used Twitter to search for information about breaking and trending stories, find potential sources, question sources, crowdsource information, get feedback about article ideas, promote stories, and chat with other journalists.

One of the most novel uses of Twitter has come from NPR’s Andy Carvin, who has combined his knowledge of Middle Eastern and North African politics, his sourcing on the ground in the region, and his social media expertise to live-tweet the uprisings that spread in early 2011 in the movement collectively known as the Arab Spring.

At the organizational level, news outlets have also used Twitter to live-blog events, create hashtags to organize conversations about particular events or issues, integrate live streams of others’ Twitter feeds around events, and add real-time commentary to live broadcasts. Among some other experiments with Twitter, The Huffington Post has launched a Twitter edition of several of its sites; The Chicago Tribune has created a fictional persona named “Colonel Tribune” to represent the newspaper’s Twitter account; and The Associated Press has run sponsored tweets by advertisers in its Twitter stream through its own arrangement outside of Twitter. On Election Day of the 2010 midterms, The Washington Post also sponsored the #election hashtag. Other news organizations have brought in revenue by setting up and helping to manage advertisers’ Twitter accounts.

Journalists have wrestled with a number of ethical issues on Twitter, including verifying breaking news and other tweets, dealing with misinformation, differentiating professional and personal communication, posting opinionated tweets, determining what is on and off the record on Twitter, and sharing too much information.

Twitter, for its part, has responded to the journalistic uses of its tool. Its Twitter Media team, in particular works with media partners both in text and in broadcast to strategize new ways to integrate Twitter into the experience of news consumers. In 2013, it hired its first data editor to analyze the data constituted by its tweets. Its executives have said Twitter doesn’t want to be a media company itself, but instead wants to partner with media companies.

Twitter also has a partnership with ESPN in which the two companies run branded campaigns around sports events and ESPN is able to post videos to Twitter, and it had also a partnership with NBCUniversal for coverage of the 2012 Olympics. It partnered with Nielsen starting in 2013 to create a social TV rating system. It also launched a guide for journalists, called Twitter for Newsrooms, in June 2011. Twitter also bought the social TV analytics firm Bluefin Labs and formed partnerships with the major TV ad buyer Starcom MediaVest Group and Fox TV in 2013.

In July 2012, Twitter briefly suspended the account of British journalist Guy Adams for tweeting the corporate email address of an executive at NBC, a Twitter partner. After much criticism, Twitter reinstated Adams’ account and published a blog post apologizing for alerting NBC officials to the post and thus prompting their complaint.

Monetizing Twitter

Twitter has been said to be valued at between $8 and $10 billion and, as of December 2010, had raised some $360 million in funding. It employed about 140 people in 2010. In its early days it was often questioned about how it would make money, though it has since done much to transition into an ad-driven media company.

One of the company’s first moves in this direction was to form search deals with Microsoft, Google, and Yahoo. In April 2010, Twitter launched an advertising program called Promoted Tweets, using tweets that advertisers pay to highlight to a wider group of users. The program became the centerpiece of its advertising strategy, which expanded into more targeted campaigns and includes an advertising API launched in 2013. Twitter has also moved into e-commerce partnerships and created a handset, TwitterPeek, in partnership with the mobile device maker Peek. In 2011, it launched Brand Pages, similar to Facebook’s and Google’s.

By 2012, Twitter was generating a majority of its revenue through mobile advertising, as about 60% of its users accessed it through mobile devices.

Twitter in politics and culture

Twitter was widely hailed as an instrumental part of Iran’s 2009 post-election protests, though several people have argued that Twitter actually played a much smaller role in the uprising than initially thought. A similar debate has taken place about 2009′s Moldovan revolution and, more recently, spring 2011′s Middle East and North African protests. Twitter’s policies regarding government censorship of tweets have been both criticized and defended by free-speech advocates.

Twitter’s detractors have called it a pointless service that encourages banality, narcissism, and incivility, allows misinformation to be spread quickly, and serves as a continual distraction to users. At the same time, though, many others have countered that Twitter can be a useful way to find and share new information — and, anyway, that Twitter is no more banal than much of the rest of our social communication.

Twitter has also been criticized for its lack of filters and dearth of informational context, as well as its corporate reservation of rights over users’ content. As a result, some have argued that the web needs another microblogging system to compete with, and perhaps also complement, Twitter.