Messaging app Signal no longer working in China
The encrypted messaging app Signal, recommended by Tesla's Elon Musk, appeared to have been blocked in China on Tuesday, closing off one of the last US social media platforms still freely available in the country.
Users of the free app, which has surged in popularity globally after rising privacy concerns, were unable to access it without a virtual private network (VPN).
China has deployed a vast and sophisticated system to scrub the internet of dissent and prevent citizens from accessing international social networking platforms such as Facebook and Twitter, in what is known as the "Great Firewall".
Signal did not immediately reply to an AFP request for comment.
The iOS version of Signal has been installed close to 510,000 times to date in China, said research firm Sensor Tower, which does not track Android downloads in the country. Google Play is unavailable in China.
Signal saw a huge surge in demand, helped by a tweeted recommendation by tech entrepreneur Musk.
The WhatsApp policy update -- later delayed -- concerned how merchants using WhatsApp to chat with customers can share data with Facebook, which could use the information for targeted ads, according to the social network.
Signal has stopped working without a VPN occasionally before, although service resumed afterwards.