Just as the FireChat app saw a spike in downloads in Iraq earlier this year when the government there started blocking access to social media sites, pro-democracy protesters in Hong Kong have also found the peer-to-peer messaging software to be a useful alternative in recent days.

The cross-platform app, which can function without the need of an Internet connection or mobile coverage, is being downloaded around 100,000 times a day in Hong Kong as protesters look for ways to deal with the problem of congested cellular networks interrupting services. The demonstrators also want to be ready in case the authorities start interfering with Internet or cellular services in an effort to disrupt the use of other social media and messaging apps.

Eager to keep up with the rapidly unfolding events in the city and stay in touch with friends, many of those present at the protests have turned to the free app, which connects mobile devices through their Bluetooth or Wi-Fi functionality.

For messages to move between devices, users need to be within about 10 meters of one another, so with thousands of people amassed in one place as they currently are in Hong Kong, information is able to flow through a crowd relatively quickly. However, as messages are not encrypted (its creators are working on it), users have been advised by the startup not to use their real names.

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The off-the-grid app – the work of San Francisco-based startup Open Garden – launched in March this year and currently has around five million users.

Stanislav Shalunov, Open Garden’s chief technology officer, told Bloomberg he was surprised by just how quickly FireChat has gained traction in Hong Kong, adding that the app is fast becoming “the de facto standard for any activist organizing protests.”

Increasing tension

Tension is mounting in Hong Kong as its chief executive, CY Leung, warned demonstrators over the weekend to end their protest by Monday or face being cleared by the authorities.

The latest unrest started just over a week ago in response to the Chinese government’s plan to vet candidates for a city leadership election in 2017.

Hong Kong was returned to Chinese control in 1997 after more than 150 years of British rule. The handover deal included a pledge by China’s Communist Party to operate the region under a “one country, two systems” arrangement that allows Hong Kong citizens greater freedoms than their mainland counterparts.

However, many of those living in the city are concerned that the mainland government is intent on dismantling the system, leading to the recent demonstrations.