Technology has played a significant role in helping Hong Kong's pro-democracy protest leaders organise their demonstrations.
But when word spread that the Chinese government might cut off mobile and internet access, demonstrators turned to a mobile app called FireChat. It relies on so-called mesh networking in which nearby devices can talk directly to each other through internal connections such as Bluetooth.
People have relied on this for the latest updates on movements and have even managed to avoid the main telecommunications network, which could be monitored.
Al Jazeera's Gerald Tan reports.
Source: Al Jazeera