Twitter said Tuesday it will start adding full-screen ads to Fleets, its disappearing tweets that sit in a row at the top of users’ mobile Twitter interface. Introduced last November, the Fleet format — a clone of Instagram and Snap’s Stories — has apparently been successful enough that Twitter now wants to try to make money from it.

“Fleet ads are full-screen billboards for advertisers,” Twitter senior product manager Justin Hoang and global product marketing manager Austin Evers wrote in a post announcing the ads. It’s partnering with a “handful” of advertisers in what it calls an “experiment,” making the Fleet ads visible to a limited group of US users on iOS and Android.

The ads support images and video in 9:16, and videos can be up to 30 seconds long. Brands can choose to add a “swipe up” call-to-action and will be able to access standard Twitter ad metrics, including impressions, profile visits, clicks, website visits, and other information.

Image: Twitter

In April, Twitter reported that its ad revenue grew 32 percent year over year to $899 million, and total ad engagement rose 11 percent. Expanding its ads beyond users’ timelines, where people can easily scroll past without engaging, seems like the logical next step. Instagram, after all, has had ads in its Stories since 2017 and started putting ads in its TikTok clone Reels last month.

Twitter CEO Jack Dorsey said during April’s Q1 earnings call with analysts that the company was still learning about who uses Fleets. “We started this product not to build a storage product within Twitter, but to solve the problem of people not wanting to tweet because they appear to be staying around too long,” he said, adding “we certainly have seen a different audience than we normally see, but we still have much to learn and a lot to figure out in terms of like, where it goes from here.”

Twitter is planning to closely study how vertical full-screen ads perform, not just for Fleet ads but possible future iterations of other full-screen formats, according to Hoang and Evers.

“We also believe that ads should be non-intrusive and bring value to people, so we’re focused on learning more about how people feel about and engage with this new placement,” the blog post states, adding that the company is planning to launch more Fleet updates soon to stickers and backgrounds.

Twitter has been on a tear announcing new features this spring, updating its warnings for potentially offensive tweets, improving its photo cropping algorithm to allow “taller” images, adding the ability for Android users to search their direct messages, and rolling out a Tip Jar feature for donations.

Twitter also acquired Scroll, the $5-per-month subscription service that removes ads from participating websites. And its long-awaited paid subscription service Twitter Blue may be coming soon as well.