Encrypted messaging app Signal stops working in China

Signal has been a popular tool among political dissidents and journalists seeking a communication method. PHOTO: REUTERS

SHENZHEN, China (BLOOMBERG, REUTERS) - Signal, an encrypted messaging app that competes with the likes of Facebook's WhatsApp, appears to have been blocked in China, the latest move by Beijing to crack down on social media platforms.

From Monday night, Signal users reported difficulties using the app in China without the help of a virtual private network, or VPN, which allows users to mask their location and access banned foreign communication services like Gmail and Twitter. Previously, no such software was needed to access Signal.

The app was still available on Apple's China app store as of Tuesday morning, and the app and website appeared to be working normally in Hong Kong.

It isn't immediately clear if this is a permanent ban, as Chinese regulators have been known to sometimes ramp up controls as a trial run only to ratchet them down later. The Cyberspace Administration of China didn't respond immediately to a faxed request for comment Tuesday morning.

Signal has been a popular tool among political dissidents and journalists seeking a communication method that minimises the risk of messages being intercepted by government censors and bad actors. In particular, the app has gained traction among China's mainly Muslim Uighur diaspora.

Open discussion of sensitive topics is off limits in China, where heavy government censorship is the norm. In February, Beijing blocked red-hot social media platform Clubhouse after it briefly provided an avenue for free-flowing debate on political matters.

Signal didn't immediately respond to an emailed request for comment sent after business hours.

Signal saw a surge in downloads worldwide after Jan 6 when WhatsApp updated its privacy terms, reserving the right to share user data, including location and phone number, with its parent Facebook and units such as Instagram and Messenger.

Signal had been downloaded close to 510,000 times on iOS in China, and has been downloaded 100 million times worldwide on the App Store and Google Play combined, according to data company Sensor Tower.

Tencent's all-in-one mobile app WeChat is China's dominant messaging app, with its payment functions and other services, boasts more than a billion users globally.

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