Instagram has officially reached 1 billion users since its launch in 2010, and the Facebook-owned social platform marked the occasion on Wednesday by launching its IGTV platform at a San Francisco event. IGTV takes on online media giants like YouTube by supporting up to one hour of vertical video content as opposed to the one-minute limit standard posts have. Content featuring online creators such as LaurDIY, King Bach and Ninja can be viewed from both a standalone IGTV app or from within the main Instagram app.

Instagram’s business blog describes IGTV as an evolution for mobile video to match with the times, citing how audiences are watching less television and more digital video, with mobile video expected to make up 78 percent of total mobile traffic by 2021. The blog also states that, according to a 2016 study by BCG, younger audiences prefer to spend time with amateur content creators instead of professionals. That explains the emphasis on online influencers, but celebrities such as Kim Kardashian West, Selena Gomez, Lele Pons and Kevin Hart have already begun to post videos on IGTV.

Brands may benefit from the platform by both partnering with influencers and creating long-form stories that serve their communities. IGTV content will play as soon as users open the app, and each creator is a channel that followers can quickly tune in to. Users won’t have to search to find content from channels that they’re already following, and swiping upward will bring up related content for them to discover.

“On Instagram, people are watching 60 percent more video than they did just last year,” said Instagram CEO Kevin Systrom at the event. “An entirely new category of video now exists, and it’s being made by creators. Teens may be watching less TV, but they’re watching more creators online.”

Systrom also said that the combined reach of Instagram’s creators is in the hundreds of thousands, giving the photo and video sharing platform “one of the largest and most engaged audiences anywhere in the world.”

Any Instagram user outside of new accounts can upload hour-long videos, but the feature will eventually expand to include everyone, and these videos support links in their descriptions that may drive traffic to external sites. Although Systrom said that the platform doesn’t support ads yet, they are “obvious” and “very reasonable” additions for the future.

Instagram won’t pay creators for content the way Facebook did to launch its Watch platform, but it is exploring ways to make IGTV sustainable by offering creators a way to monetize their content, and ad revenue shares could be among those methods. According to eMarketer, Instagram is expected to pull in $5.48 billion in ad revenues this year, and brands may be eager to address this still-growing audience as they shift spending away from television and Facebook’s rising ad costs.

With IGTV, Instagram is heating up the competition with both YouTube and Snapchat, and although the latter platform has vertical TV shows that attract 20 to 30 million viewers per month, they tend to be either short—around three to five minutes—or comprised of multiple Snaps.