Twitter Inc. is expanding its version of Stories, a product that lets users post photos and videos that disappear after 24 hours, in an effort to encourage more sharing.

Twitter has been testing the product, called Fleets, in international markets like Brazil and India, and beginning Tuesday is making it available globally, including to users in the U.S. The company launched Fleets in March, hoping to capitalize on the popular Stories feature that was invented by Snap Inc.’s Snapchat and later spread globally by Facebook Inc., which copied it into all of its apps.

Twitter also teased a new audio product called Spaces, which works like a kind of group voice call among users who have been invited to participate, company executives said Monday. But the feature is still being developed and won’t be tested until later this year, they said.

Both products are meant to give people more places to interact with one another on Twitter, including in ways that aren’t necessarily public or visible on a user’s profile over the long term. Company executives said research has shown that many users are too intimidated to post or engage with others on the service, which has led to an effort to find new ways to spark interaction.

“Tweeting, retweeting, engaging in conversation can honestly be incredibly terrifying,” said Nikkia Reveillac, Twitter’s head of research. “We do not know how others will react to us, we do not know if anyone will reply, and we do not know if anybody will even care.”

Fleets offers another venue for Twitter to sell advertising, and the feature has been lucrative for competitors. It’s estimated that Instagram Stories is responsible for 10 per cent of all Facebook advertising, for example. Facebook reported more than US$21 billion in advertising revenue in the third quarter. A Twitter spokeswoman confirmed the company is considering putting ads inside the product, but is not yet doing so.

Audio is another area where Twitter has shown interest this year. It launched an audio tweets product in June so users could tweet out a recording. Twitter’s new Spaces feature is similar in concept to Clubhouse, a startup that has gained attention in Silicon Valley. That app creates virtual hangouts for people who wish to swap ideas or discuss a particular topic, but has drawn criticism for failing to police its chats.

“Audio is interesting for us,” said Kayvon Beykpour, Twitter’s head of product. “When you can hear someone’s voice you can empathize with them in a way that’s just more difficult” over text.