In the midst of devastating wildfires sweeping through Los Angeles, a free app called Watch Duty has emerged as a crucial lifeline for millions of people. The 501(c)(3) non-profit behind the app has taken a unique approach, prioritizing accuracy and speed of information over user engagement and ad sales. As a result, Watch Duty has rocketed to the top of Apple's and Google's app stores, with over 1 million downloads in just a few days.

The app's simplicity and elegance lie in its lack of user data scraping, ads, or login requirements. Instead, it provides critical information on active fires, mandatory evacuation zones, air quality indexes, and wind direction, making it an indispensable tool for firefighters and residents alike. Watch Duty accepts tax-deductible donations and offers two tiers of membership, unlocking additional features such as firefighting flight trackers and customizable alerts.

The idea for Watch Duty was born out of the Walbridge fire in 2020, when cofounder John Mills struggled to find reliable information to protect his off-grid Sonoma County home. He teamed up with friend David Merritt, Watch Duty's CTO, to build an app that would provide a single source of truth for people to protect themselves from wildfires. The app was built in just 60 days by a team of volunteer engineers and reporters, with a focus on simplicity and reliability.

Watch Duty's founders view their app as a public service, providing timely and relevant information for people's safety during emergencies. This approach is a stark contrast to the piecemeal alert systems used by governments, which can cause delays that cost lives. Watch Duty's push notifications are designed to reach users in under a minute, with 1.5 million people in LA currently receiving critical updates through the app.

The app's technology stack is built on a mix of platforms, including Google's cloud platform, Amazon Web Services, Firebase, Fastly, and Heroku. While Watch Duty uses some AI for internal routing of alerts and emails, its reporters – mostly volunteers – are the backbone of the app's success. These reporters listen to scanners and update the app with push notifications, adhering to a strict code of conduct that prioritizes quality over quantity.

Despite starting with volunteer engineers, Watch Duty has slowly added more full-time staff as it grows. The app boasts 100 percent uptime, with no plans to charge for its services or scrape user data. Instead, the non-profit relies on donations and partnerships with corporate sponsors to provide its critical service.

However, Watch Duty's reliance on publicly available information from government agencies like the National Weather Service and the Environmental Protection Agency raises concerns about the potential impact of policy changes. Should the incoming Trump administration follow through on threats to dismantle these agencies, Watch Duty's ability to operate could be affected. Nevertheless, Merritt remains optimistic, stating that the app will be "pretty well insulated" from policy changes and is willing to take on the cost of buying data from government agencies if necessary.

As Watch Duty continues to expand its services across the United States and beyond, its impact on emergency response systems cannot be overstated. With plans to roll out nationwide soon, the app has already become a critical tool for millions of people in Southern California. As Merritt notes, "We got 1.4 million app downloads in the last few days... I think we have only received 60 support tickets, so that shows that something is working there."

In a world where technology is often driven by profit and user engagement, Watch Duty's commitment to providing a free, reliable, and critical service is a breath of fresh air. As the app continues to grow and evolve, its impact on emergency response systems and people's lives will only continue to increase.