We’ve all experienced that moment of panic when we think we’ve lost our phones. After a frenzied search of every room in the house and each nook and cranny of the car, it usually turns up. But what if you’re not at home? What if you’re in a crowded public place?

That was me in the George Bush Intercontinental Airport last Friday afternoon. I had slid my phone into my pocket before going through security. After being scanned, the TSA agent asked me to hand over my phone, so she could do a pat down. She handed it to another agent and over the next few minutes, the phone disappeared. It did not come through on the conveyor belt with my bag, and the agent who had taken my phone was nowhere to be found. To their credit, the TSA crew scoured the area and reviewed the video footage, but no phone. They decided someone had picked it up and left.

Meanwhile, my assistant who was traveling with me asked me to log into my Apple account on his computer. A few minutes later, a sheepish couple walked toward the security area holding my phone. I have never paid much attention to Apple’s built-in feature, but it’s a lifesaver, and I want to share it with you so you will know exactly what to do if you find yourself in a similar situation.

With the iOS 13 update, Apple merged the Find My Friends and the Find My iPhone apps into one app that’s called “Find My” and allows you to find a lost device even when you don’t have a WiFi or cellular connection. If your device is registered with Apple, it will appear within this app. Almost all Apple products are Find My compatible, including iPhone, iPad, Macs, Apple Watch and AirPods.

Take a moment to familiarize yourself with the app, which opens to a map that shows the location of each of your devices, as well as people you are sharing location data with and yourself—switch between these options at the bottom of your screen. While the app has a number of functions, we’re going to focus on what to do when you lose your phone.

In a public place like an airport or restaurant, time is critical. Do not spend precious minutes looking for your phone; let the app check for you. Now here’s the tricky part: You must go online to use Find My, which may mean using a laptop you have with you, a friend’s phone or a willing stranger. If you travel alone, you should consider carrying a spare phone for just this emergency. It doesn’t need to be fancy, it just has to connect to the internet. Go to icloud.com/find and log in with your Apple ID and password. If you haven’t committed this to memory or are worried you may forget, write your login credentials on a small slip of paper and put it in your wallet.

Once you’ve logged into your account, tap Devices and then your phone to see its location on the map.

You can zoom in to get a better picture of its location. For whatever reason, the location was not precise enough for me in Houston. I couldn’t tell if the phone was still in the security area or the food court across the walkway. You can also play a sound on the lost phone, but this will only be helpful if it is buried in your bag or very close by. Your best option is to Mark As Lost by tapping Activate. You will be asked to enter a phone number that can be called by the person who has or finds your phone. A message saying “This phone has been lost” and the number to call will appear on the phone’s screen.

By activating lost mode, your phone will be locked and Apple Pay will be disabled. If your phone contains sensitive information, you can use “Erase This Device” found under the lost activation link.

With the iOS 13 update, you can also locate a device that is not connected to WiFi or a cellular service by using Bluetooth. You must have Bluetooth turned on to take advantage of this capability, which you will find in your phone’s Settings. But keep in mind this is for short range location only. Walk in ever-expanding circles to try to locate your device if it has not appeared on your map.

If a travel companion or a panicked stranger has lost a phone, you can easily come to the rescue. Open your Find My app, go to Me and then tap on Help A Friend, which will open iCloud so that the person can log into their account and start the process.

Leslie Meredith has been writing about and reviewing personal technology for the past eight years. She has designed and manages several international websites and now runs the marketing for a global events company. As a mom of four, value, usefulness and online safety take priority. Have a question? Email Leslie at asklesliemeredith@gmail.com.

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