More than 10 million people have signed up to Threads, Meta’s rival to Twitter, within the first few hours of its launch, the company’s CEO Mark Zuckerberg said on Thursday.

According to Dawn, the app went live on Apple and Android app stores in 100 countries at 2300GMT on Wednesday, and will run with no ads for now, but its release in Europe has been delayed over data privacy concerns.

Threads is the biggest challenger yet to Elon Musk-owned Twitter, which has seen a series of potential competitors emerge but not yet replace one of the world’s biggest social media platforms, despite its struggles.

“10 million sign ups in seven hours,” Zuckerberg wrote on his official Threads account on Thursday.

Here’s THREADS’ entire sign-up process.

This is so clean. So easy.
– instantly get your Instagram @ handle
– auto imports your bio + pic from IG
– instantly follow from your IG

Reallyyy genius way to launch an app. pic.twitter.com/h5yVTZgUI2

— Jack Appleby (@jappleby) July 5, 2023

Accounts were already active for celebrities such as Jennifer Lopez, Shakira and Hugh Jackman, as well as media outlets including The Washington Post and The Economist.

Zuckerberg also offered a shot across the bow at Musk — the pair are known to be bitter rivals.

In his first tweet in over a decade, Zuckerberg posted a Spiderman pointing at Spiderman meme in an apparent reference to the similarities between Threads.

On Threads, he wrote: “It’ll take some time, but I think there should be a public conversations app with 1 billion+ people on it. Twitter has had the opportunity to do this but hasn’t nailed it. Hopefully we will.”

Zuckerberg is widely understood to be taking advantage of Musk’s chaotic ownership of Twitter to push out the new product, which Meta hopes will become the go-to platform for celebrities, companies and politicians.

Analyst Jasmine Engberg from Insider Intelligence said Threads only needs one out of four Instagram monthly users “to make it as big as Twitter”.

“Twitter users are desperate for an alternative, and Musk has given Zuckerberg an opening,” she added.