Coalition is a global, privacy-first exposure notification app to help stop the spread of COVID-19. Given that the vast majority of phones are Bluetooth-enabled, each time a phone passes by another phone or other Bluetooth-enabled device, it picks up anonymous device information. If a Coalition app user declares that they have tested positive for COVID-19, their phone then can anonymously and almost instantaneously inform all other phones that have been in its proximity over an extended period of time during the prior 2 weeks. The amount of exposure period and the length of time we trace back to can be set by epidemiologists. Users who are notified can then immediately take necessary self-isolation measures. The identities of both the COVID-19 positive patient and of the people receiving the notifications are securely encrypted. Coalition benefits from decade-long R&D in the space of decentralized wireless networks, mobile mesh and secure identity management systems from the Nodle (http://nodle.io) team. The technology was developed by the team at Nodle—the world’s largest ecosystem of connected devices, providing low cost, secure wireless infrastructure + data insights for enterprises, manufacturers and smart cities. The Nodle founding team previously created FireChat, a peer-to-peer Bluetooth-based messaging technology that has been used to stay connected and communicate while in planes, on cruise ships, at large festivals, during internet shut down and in cases of disaster-recovery situations. We were introduced to Dr. Philip Milne, the author of this Medium post Coronavirus: a viable technology-based containment strategy and realized we were uniquely placed to apply our know-how and make this happen fast. We believe that the whole of humanity is concerned by what is happening. In these times of great uncertainties and of emergencies we have to act fast. It is an opportunity to use our software and expertise for good to save millions of lives.