The app saw a surge in users this week with nearly 2 million downloads from Los Angeles area residents, nearly doubling its user base.

While the destructive Los Angeles fires rage, all eyes have turned to the app that lets you track them. WIRED spoke with Watch Duty founder John Mills about how the platform has met the moment.

As multiple wildfires spread across Los Angeles, local have rushed to download the Watch Duty app to get the latest fire news and maps. Here’s how it works.