TikTok has gone dark across the US - affecting 170 million American users - after the Supreme Court ruled against its bid to avoid a ban that has shut the app down.
The ban is the end result of 2024 legislation passed on national security concerns that called for TikTok parent ByteDance to sell the popular short-video app or see it shut in the US on 19 January.
Donald Trump, who takes office on Monday, has said he would try to find a "political resolution".
Speaking to NBC News' Meet The Press moderator Kristen Welker on Saturday, the president-elect said he was considering giving TikTok more time to find a buyer.
Mr Trump told Sky's US partner network in a phone interview: "I think that would be, certainly, an option that we look at.
"The 90-day extension is something that will be most likely done, because it's appropriate. You know, it's appropriate. We have to look at it carefully. It's a very big situation.
"If I decide to do that, I'll probably announce it on Monday."
The federal law allows the sitting president to extend the deadline by 90 days if a sale is in progress. But no clear buyers have emerged, and ByteDance has previously said it won't sell TikTok.
Below are the answers to some key questions:
What has happened to the app?
TikTok's app has been removed from prominent app stores in the US so can't be downloaded.
When existing users opened the TikTok app on Saturday evening, they encountered a pop-up message from the company that prevented them from scrolling on videos.
"A law banning TikTok has been enacted in the US," the message said. "Unfortunately that means you can't use TikTok for now."
"We are fortunate that President Trump has indicated that he will work with us on a solution to reinstate TikTok once he takes office," the message said.
"Please stay tuned!"
Some of the so-called "TikTok refugees" have been turning to a Chinese app called Xiaohongshu - aka RedNote.
It is a lifestyle social media app which allows users to post short videos, photos and texts, and it also includes functions like live-streaming and shopping.
Read more:
What is RedNote?
How are users affected?
It was thought that TikTok's estimated 170 million users in the US would still be able to use the app because it was already downloaded on their phones - but that is not the case.
A web-based version of the service might be accessible that has fewer features than the app, but even that might not work, experts have said.
Some users could try to access TikTok through virtual private networks, or VPNs, which can conceal the internet protocol, or IP, address of a user and thereby their location.
Content creators who have built businesses from their TikTok followings have been preparing for the app's shutdown and were redirecting their followers to alternatives such as Instagram and YouTube.
What do the content creators say?
Tiffany Cianci told the Associated Press the ban shows "our elected officials failed the American people in failing to learn what TikTok actually meant to the American population".
"In reality, it's an ecosystem that has created a huge portion of the American economy.
"It's created a place where seven million small businesses thrive in ways that they're not able to thrive in any other economic social media system in the United States."
Influencer and creator Janette Ok said the platform helped her make brand deals and promote her music - bringing "opportunities that I never believed I could experience in my lifetime".
"It's a beautiful app, it's brought so many people together, it's changed a lot of people's lives, and for it to just be taken away like that feels... so not American," she said.
What will advertisers do?
Advertisers have rushed to prepare contingency plans as the ban jeopardises their campaigns on the platforms.
TikTok has continued to pitch advertisers on new features, like a tool launching in test form that would make it easier to create, modify and add advertisements in bulk.
The ban means more than $11bn in annual US ad investment is up for grabs.
The ban could worsen trade tensions between the US and China that were already strained after export curbs on advanced American semiconductor technology to Beijing.
Mr Trump could try to use an executive action to protect TikTok for his four years in office, but he could use the risk of him changing his position to extract something meaningful from China, according to analysts at LightShed Partners.
What impact could the ban have on UK users?
There is no suggestion that the US ban would directly affect users in the UK, where technology is regulated by British legislation. However, UK TikTokers, who create content on social media for a living, have expressed fears over how the ban might impact their viewership and incomes.
Aidan Halling, also known by his handle @etherealgames on TikTok, creates comedy skits on gaming for his 30,000 followers, and is concerned his income may take a hit as the ban could force him to ditch the app.
"A lot of creators rely on this app for a living, and it's about to be pulled away from under them," he told PA news.
"This ban could potentially force me to pivot to different content or stop posting all together. While 15% of my followers are American, around 40% of initial video views are from the US."
(c) Sky News 2025: Time's up for US TikTokers: What does this mean for users and content creators?