Signal is one of the various instant messaging apps available on iPhone and Android that offer end-to-end encryption. The chats can be accessed by anyone else other than the parties involved in it. iMessage and WhatsApp provide similar functionality by default, while Telegram’s end-to-end encryption needs to be enabled for each separate chat.
That sort of strong encryption has made surveillance operations more difficult in the past few years, with various governments attempting to either ban encrypted devices and apps or argue for backdoors that would allow law enforcement to collect data from suspects in criminal cases. That’s the sort of approach seen in Western countries that could one day threaten encrypted products. China has a different weapon in place. The country just blocked Signal. The app can still be used in China, but the process involves using an additional service.
According to TechCrunch, Signal is not available in mainland China as of the morning of March 16th. Censorship tracking website Greatfire.org says the Signal app and website have been banned on March 15th.
The app remains listed in Apple’s App Store for China, but it’s unavailable on Android devices running local digital stores. Google’s Play store isn’t available in China. It’s only iOS users that can download Signal on iPhone and iPad. Like with Telegram and WhatsApp, users will need to run a virtual private network (VPN) on their devices to run Signal. Without a VPN, these apps would not work in China.
Similarly, China blocked Facebook, Twitter, and Instagram in the country. The addition of Signal to that list further proves the app is growing in popularity even beyond China’s Great Firewall.