TikTok officially went offline for more than 170 million Americans on Sunday as company officials put the China-owned app’s future in the hands of President-elect Trump.

A looming ban on TikTok set to take effect on Sunday presents a multibillion-dollar headache for app store operators Apple and Google.

A law that prohibits mobile app stores and internet hosting services from distributing the video-sharing platform to U.S. users takes effect on Sunday.

The clock is ticking toward TikTok's end with a possible ban set to go into effect Sunday. Here's where "TikTok refugees" are going.

NBC News reports that TikTok has boosted advertisements for Lemon8, an application also owned by ByteDance, in recent days. Rival social-media apps and websites such as Instagram, YouTube, and Snapchat are expected to increase their user base in the wake of a possible ban.

Even with any assurances from Donald Trump, companies like Apple, Google, and Oracle would be taking a risk by not complying with the TikTok ban.

TikTok is set to be banned tomorrow. Here's what time the ban could start in the U.S. and what the app could look like for users trying to access it on Sunday.

The incoming president said he will “most likely” give TikTok a 90-day extension called for in a law upheld by the Supreme Court yesterday to see it sold or banned by a deadline tomorrow. In a phone interview with Meet the Press moderator Kristen Welker of NBC News,

TikTok creators are posting videos promoting ways to get around a looming shutdown of the app in the US, which could spell trouble for Apple Inc., Alphabet Inc.’s Google and other American tech companies required by law to enforce the ban or risk potentially billions in fines.

Duolingo shares have jumped this week, as the number of Americans learning Mandarin on the app has soared 216%. That's as China's RedNote is now the most downloaded free app on Apple's App Store ahead of the TikTok ban.