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Twitter has struggled with slowing user growth and engagement which has concerned investors. Shares in the San Francisco-based company are down over 24 percent this year. But the microblogging site has been introducing services to keep eyeballs on its app for longer. Earlier this year it tested a "buy now" button to allow users to buy products directly from a tweet.
"With this, it is again another service aimed to keep people engaged within the app," Jack Kent, senior mobile analyst at IHS, told CNBC by phone.
"In broadening out the content, they hope people will stay in the Twitter environment."
Twitter has also got iTunes on board so users can listen to music in their timeline then be transferred to Apple's service to buy the song. Rock band the Foo Fighters officially launched their new single "Something From Nothing" on Audio Card.
"We're just beginning to test the Audio Card and plan to make it available to more partners and creators in the future so that many more musical artists and creators will be able to share exclusive, in-the-moment audio to millions of listeners on Twitter," the company said in a blog post.
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