This article originally appeared on VICE ASIA.

Five university students sat on two beds in a hotel room one night in October. They were in Mong Kok, a densely urban district of Hong Kong considered a hotspot for the pro-democracy protests that have rocked the city since June. With live coverage of the protests playing on the room’s TV, and laptops and smartphones on queue, they were waiting for requests for rides home from the front lines of the rallies via the cloud-based messaging app Telegram and forum LIHKG.

They run an operation called the “Uber” of the protest movement. Telegram’s channel function allows them to reach an unlimited number of users, who can offer or request rides anonymously and with no digital record of the exchange. Following a “state-actor sized” cyberattack in June, that Telegram said appeared to come from China, the company upgraded its security settings so that users don’t need to link their accounts to a phone number.