How to use the Apple Watch ECG app

A new app on the Apple Watch Series 4 can help you monitor your heart's health.

Jason Cipriani Contributing Writer, ZDNet
Jason Cipriani is based out of beautiful Colorado and has been covering mobile technology news and reviewing the latest gadgets for the last six years. His work can also be found on sister site CNET in the How To section, as well as across several more online publications.
Jason Cipriani
3 min read
James Martin/CNET

Apple on Thursday released its ECG app for the Apple Watch Series 4 via a software update. The ECG app uses the watch's digital crown and sensors along the bottom of the watch to monitor the electrical patterns of your heartbeat and analyzes it for potential issues.

That's a rather simplified breakdown of the new app -- if you want a deeper dive you can read more about it here. Also, be sure to read Vanessa Hand Orellana's experience when she tested the ECG app prior to launch.

So how do you use it? Let's take a look. 

Read more: All of the WatchOS 6 updates | Complete guide to Apple's Health app | 18 devices that sync with Health App 

What's required

You'll need to update your iPhone to iOS 12.1.1, and your Apple Watch Series 4 to WatchOS 5.1.2 in order to use the ECG app. Read about the update process for the Apple Watch here.

ECG vs. EKG: What's the difference?

Nothing. The two abbreviations are interchangeable, and refer to the same test, an electrocardiogram, according to the American Heart Association.

EKG is the more common abbreviation for the test (so as not to be confused with an EEG, a brain scan), but Apple uses ECG to refer to the feature on the Apple Watch.

Keep in mind that this test isn't a substitute for diagnosing a heart attack, stroke or other health conditions. If you feel like you're having a severe health issue, call 911 or visit your doctor as soon as possible. Don't rely on the ECG app.


Screenshots by Jason Cipriani/CNET

Before you can take your first reading, you'll need to open the Health app on your iPhone. The first time you launch the app after updating, you'll be asked if you want to setup the ECG feature, which means entering your birthdate and reading through a guide of what the feature can and can't do.

How to use it

With setup complete, look for the ECG app icon on your watch's app grid. It's a white circle with a red line that looks similar to a heart rate reading; tap it. 

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In order to capture accurate results, you'll need to have your arms in your lap or on a desk and leave a finger placed on the Digital Crown for the duration of the countdown. Try to remain as still as possible, as any movement can impact the test. 

Make sure your watch is fit tight on your wrist, and that you have the proper wrist location identified in the Watch app. 

Screenshots by Jason Cipriani/CNET

Once the 30-second test is complete, you'll receive one of three results: Sinus rhythm, atrial fibrillation (AFib) or inconclusive. A sinus rhythm means your heart is beating in a uniform pattern. AFib means your heart is beating in an irregular pattern. Inconclusive means either the app had a hard time getting a reading due to movement or other factors, or the heart's rhythm doesn't qualify for either sinus or AFib.

Apple Health app

Screenshots by Jason Cipriani/CNET

After each EKG test, the Health app will notify you of the results on your iPhone. Open the alert to view a chart of your heart's rhythm, and any relevant advice or actions Apple recommends you should take.

If you want to show a doctor your recording, you can export a PDF that contains a chart of your heart's activity when viewing any specific EKG in the Health app.

Apple Watch Series 4: Both sizes, compared

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Apple Watch Series 4 review: Bigger, faster, even more health-conscious.

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