After a classified intelligence review, Apple removed ToTok from the App Store, and a New York Times report said the app was a spy tool used by the UAE.
The chat app was revealed to feed highly sensitive personal data to the UAE government, and became one of the most downloaded social apps in the U.S. last week.
The NYT piece said the popularity of ToTok was first established in the UAE, where other messaging apps are banned but have taken off in the US and elsewhere since then.
According to the report the U.S. intelligence services were already aware of this, advising allies not to use it.
Since the app does not use end-to-end encryption, all messages could be read freely by the service.
After they were contacted by the NYT, both Apple and Google removed the app from their stores.