Don't know what your definition of "world" is, but people in China (that's 1.3b people) don't have access to WhatsApp, and the "default" chat app WeChat is moni

Don't know what your definition of "world" is, but people in China (that's 1.3b people) don't have access to WhatsApp, and the "default" chat app WeChat is monitored by the police at all time. So maybe you want to be a bit more accurate with wording.