Here's how to use Zello, the walkie-talkie app people are scrambling to download as Hurricane Florence floods the Carolinas

Mark Wilson/Getty ImagesThe North Carolina coast ahead of Florence

Hurricane Florence made landfall at Wrightsville Beach, North Carolina, Friday morning. As people prepare for the worst, and a free smartphone app has risen to the top of the App Store charts.

Called Zello, the app lets you use your phone as a walkie-talkie or two-way radio as long as you have a network or WiFi connection. Users can join channels and instantly send messages or photos, and the app even works over older 2G networks.

Earlier this week, Zello was ranked No. 4 among social networking apps in the US, as well as No. 38 among all iPhone apps overall. According to app analytics firm Sensor Tower, that was a major jump from just one day ago – on Monday, Zello was ranked No. 25 among social networking apps and No. 389 overall.

Now, Zello is ranked No. 1 overall in the App Store.

This isn’t the first time Zello has come in handy. Back in August, Zello saw a significant jump in new installs as Tropical Storm Lane approached Hawaii. And last year, Zello reached No. 1 on the App Store as Hurricane Irma ripped through the Caribbean.

If predictions hold, Hurricane Florence may be the strongest storm ever to make landfall north of Florida. It’s important to note that if cell towers are wiped out in the storm and WiFi goes down, Zello will not work. But if you have cell service – even a 2G or 3G connection – the app could help in the event of an emergency.

Here’s how it works.

Zello is free to use and doesn’t have ads. To start using the app, though, you’ll need to make an account. You can provide as much or as little information as you’d like, including a photo, description, and voice greeting.

Zello/Business Insider

Zello takes a no-frills approach to its interface. By clicking the menu button, you can check your volume level, change your status, view your contacts, and see available channels.

Zello/Business Insider

Zello lets you join existing channels or create your own. To check out some of the available channels, click “Channels” in the menu, then navigate to “Trending Channels.”

Zello/Business Insider

You can also search for a specific topic, like Hurricane Florence. When you click on a channel, you’ll get an overview of what people are talking about before you join.

Zello/Business Insider

Once you join a channel, you’ll hear audio from other members right away, much as if you were listening to a police scanner. You can hear everything posted in the channel. When I listened, I mostly heard people checking to see if the app worked for them as they prepared for the storm.

Zello/Business Insider

Once inside a channel, you can also see a list of users and listen to some of the voice messages people have posted.

Zello/Business Insider

If you don’t want to listen to the audio transmissions, you can turn them off by tapping the power button. You’ll still be a member of the channel, but the sound will be muted.

Zello/Business Insider

If you want to transmit a message, just press the record button. You can also send a photo by clicking the camera button on the left. Your message will post to the channel, where anyone can listen to it and respond.

Zello/Business Insider

<h2>Read more of Business Insider’s hurricane coverage:</h2><ul><li><a href=”″>Photos and videos show the flooding and devastation as Hurricane Florence hits North Carolina</a></li><li><a href=”″>Hurricane Florence has 150 trapped, stranded as flood waters swallow small North Carolina town</a></li><li><a href=”″>Weather Channel video illustrates the horrifying reality of towering floodwater in North Carolina</a></li><li><a href=”″>Hurricane Florence could dump up to 40 inches of rain on parts of the Carolinas &mdash; here’s why the deluge may be so intense</a></li><li><a href=”″>The 14 most important things you should do to prepare for a hurricane</a></li><li><a href=”″>’Watch out, America!’: Astronauts in space photographed Hurricane Florence, and they say the view is ‘chilling'</a></li></ul>

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