Zello, the smartphone app, has been trending on both the Play and Apple Stores this week as a huge number of people downloaded it in anticipation of Hurricane Florence. But what is Zello, and how might it help amid a catastrophe?

On its store page, Zello portrays itself as a “fast and simple walkie-talkie app” that works over Wi-Fi or your phone’s cellular network.

How it works:

Once your friends and family have the application and join, you can put them all in a single, private group chat. From that point on, the network functions as a  walkie-talkie radio. Press the virtual microphone in the app, and everybody in the group can hear what you’re saying in real time.

Since it runs in the background, you can multitask while hearing anyone in the group chat.  You can likewise send text and picture messages to individuals privately or the group chat. Additionally, there are many public channels you can join where you can keep track of the storm with different users, call for help, or just chat.

Nonetheless, the app does not transform your phone into an actual walkie-talkie. Walkie-talkies utilize radio waves through short distances. Whereas Zello still requires either an Internet connection or weak phone signal.

Zello was especially popular in 2017 when Hurricanes Irma and Maria hit, to such an extent that Zello created a list of tips on how to use the app during a natural disaster.