How badly does the photo-sharing app Instagram covet young users? On Thursday, it introduced the most expensive brand campaign in the app’s history, according to Meta, and it is squarely focused on Gen Z.

“We’re 15 years old now, and I think one of the core challenges we face is: How do we stay relevant?” Adam Mosseri, the head of Instagram, said in an interview.

The campaign, a series of digital advertisements and billboards featuring stars like the musicians Rosalía and Tyler, the Creator, casts Instagram as a launchpad for scrappy creative types. (As opposed to, perhaps, a social media behemoth whose owner, Meta, is facing a landmark antitrust trial.) It is just one way in which Meta is acting on its long-simmering anxiety that Instagram risks being written off by a younger generation that expects a looser, less manicured social media experience.

“It’s just a lot less pressure posting on TikTok,” said Sheen Zutshi, 21, a college student in New York. She uses Instagram to send direct messages to her friends, but sees it as a more curated option — the sort of place where someone might earnestly post a photo of the night sky, like her older cousin did recently. “It’s just really cute, because she’s a millennial,” she said.

Instagram is the third most widely used social media site among teenagers, behind YouTube and TikTok, according to a 2024 report from Pew Research. In a survey conducted this spring by the investment bank Piper Sandler, nearly half of teenagers said they considered TikTok their “favorite” platform.

In interviews, a dozen members of Gen Z, ranging in age from 15 to 26, said they still used Instagram to keep in touch with friends, scope out crushes, build businesses and pore over cooking videos, despite worrying at times about the app’s effects on their mental health. But out of all of its features, they seemed least interested in the polished, public photo feed that had once been Instagram’s marquee offering.