A hot potato: TikTok and WeChat are set to be banned in the United States starting Sunday, September 20, on all app stores and platforms, unless President Trump makes a decision on a last-minute deal. The move comes as the Trump administration claims that both apps pose a threat to national security, and could pass user data on to China. TikTok, WeChat, and the Chinese government all deny the accusations.

Follow-up: Trump approves Oracles's TikTok bid "in concept" - Tick tock, tick tock... ban has been delayed by a week while new deal is finalized

Update #2: A judge in California has temporarily blocked the US Commerce Department's ban on WeChat which would have come into effect Sunday night. While not as popular as TikTok, WeChat is estimated to be used by around 19 million users in the United States, as it's popular with Chinese students, and Americans who have personal or business relationships in China.

TikTok has tried working with the U.S., claiming it has offered "unprecedented levels of additional transparency" in recent days. Tencent, owner of WeChat, will also continue talks with the U.S. in an attempt to achieve "a long-term solution."

President Trump signed an executive order banning the apps in August. It gave U.S. businesses 45 days to stop working with the companies. In the order, Trump wrote, "The spread in the United States of mobile applications developed and owned by companies in the People's Republic of China (China) continues to threaten the national security, foreign policy, and economy of the United States."

TikTok has rocketed in popularity over the last year, especially among younger users.

Out of its 800 million-strong user base, some 30 million are based in the U.S. But, despite its popularity, there have been numerous privacy concerns. It's already been banned by Joe Biden's staff, the Navy, and the TSA, among others.

As it stands, there are two different timeframes for both apps. A full ban on WeChat is going into effect this Sunday, September 20. On the same date, a ban on updates and maintenance to the TikTok app will be in place, with a view to banning TikTok entirely on November 12 - unless satisfactory changes to the app's services are made.