One of the most popular apps in the Middle East has been used by Emirati authorities to reportedly spy on millions of users. Cybersecurity researchers said the app's design would allow it without exploits or backdoors.

Axar.az reports citing DW that US officials "familiar with a classified intelligence assessment," the newspaper said the app allows it to "track every conversation, movement, relationship, appointment, sound and image of those who install it on their phones."

The app has topped charts in the UAE and boasts users from Europe, the US and the wider Middle East, among other regions and countries.