Apple Watch Series 4 Review: A Big Deal for Our Health

A few days ago, I sat in a medical recliner at the University of California, San Francisco. A cardiologist placed 10 stickerlike electrodes onto my limbs and chest and then connected the wires to a dated-looking contraption with a screen and a keyboard on a cart.

About a minute later, a printer produced a chart of my heart’s electrical activity on red graph paper. The procedure I had undergone was an electrocardiogram, or an EKG, which is used to diagnose cardiac problems like arrhythmia and heart attacks.

I took the test to gain a better understanding of the implications of the Apple Watch Series 4, Apple’s new smart watch, which will become available Friday. For the first time, the watch includes an electrical heart sensor that will eventually work with an app that takes EKGs. When the EKG app, which has been approved by the Food and Drug Administration, is released this year, we will be able to place a finger on the watch’s crown to measure the electrical charges across our hearts.

The Apple Watch’s EKG won’t be nearly as comprehensive as the one produced by a traditional electrocardiograph, which hooks up to multiple parts of the body, like the one the cardiologist used on me. The watch is a single-lead EKG device, meaning it will record one angle of the heart’s electrical signals — enough to collect data about arrhythmia but not to diagnose a heart attack.

Still, the new Apple Watch is perhaps one of the most significant developments in wearable gadgets in years. People with heart problems can easily use the EKG app to take electrocardiograms whenever they sense something abnormal, without the rigmarole I went through. And the data can be shared immediately with their doctor, which could open a conversation about next steps, like going in for a visit or modifying treatment.

For everyone else who doesn’t have a confirmed heart condition, this feature will not immediately be a selling point.

“I’m not recommending it for most people as anything other than just a novelty,” said Dr. Ethan Weiss, the cardiologist who took my EKG.

But he added that the implications for heart research were profound. “There’s all this stuff we don’t know,” he said. Typically, an EKG in a doctor’s office provides up to 90 seconds of data. “We’re only getting little snippets,” Dr. Weiss said.

Much of the rest of the Apple Watch Series 4 sounds boring on paper. Compared with its predecessors, the fourth-generation smart watch has a slightly larger screen and is faster at tasks like loading apps.

Yet the watch’s evolution from a fitness tracker into a health-monitoring device makes it vastly more interesting in the long term. Apple often sets the standard for consumer electronics, so the watch may prompt other companies to create a generation of wearable devices that help people gather information about their health conditions.

In the meantime, I tested the new Apple Watch for a week and found it incrementally better than the previous version. Here are the highlights.

A higher price, a larger screen and faster speed

The most apparent changes to the new Apple Watch show up in its higher price and larger screen and case.

The new models start at $399, compared with $329 previously. The two sizes are 40 millimeters and 44 millimeters, up from 38 millimeters and 42 millimeters. But while the case is now slightly longer and wider, it is also thinner, and the 40-millimeter model didn’t feel bulkier than the 38-millimeter Apple Watch that I used in the past.

More important, the screen stretches out from one edge to the other, letting apps take up more of the watch’s face. This enlarged display makes everything on the watch look better, including text.

A less obvious, though still useful, change is the watch’s speed. Apple emphasized that the device was two times faster than the third-generation model, which was already zippy.

The speed difference was most noticeable when using Siri, Apple’s voice assistant. By simply raising the watch toward my mouth, I could speak a command like “Set a timer for 20 minutes,” and the watch reacted with barely any delay. The hands-free ability to summon Siri is a feature of Apple’s new watch operating system, WatchOS 5. In my book, this is how watches were meant to be used: without having to press any buttons.

A superb fitness tracker

To test the watch’s fitness-tracking capabilities, I wore it on a 7.7-mile hike in Pacifica, Calif. I opened the Workout app on the watch, chose hiking as a workout and paid close attention to the device’s tracking of my walking distance and heart rate.

Throughout the hike, I wondered about my progress. How many miles to the end of the trail? Had I gone too far and gotten lost?

The Apple Watch relieved me of anxiety by updating the distance I had hiked for every tenth of a mile. By the end of the trek, the Apple Watch said I had hiked precisely 7.7 miles. Impressive accuracy.

During steep inclines throughout the hike, I glanced at the watch to check my heart rate. With past Apple Watch models, there was a delay before they showed me. But the new model, with its improved speed, updated with my current heart rate almost instantaneously.

Who should buy the Series 4?

While the Apple Watch Series 4 is a solid piece of technology and another step toward the maturity of wearable computers, I wouldn’t recommend it for people who are considering a smart watch for the first time.

Here’s why: $399 is a stiff price to pay for a gadget with lightweight utility. Fortunately, Apple is selling its older Series 3 watch, which I rated as a great product last year, for $279. Now is a good time to get the older one.

I wouldn’t upgrade to the Series 4 from a recent generation of Apple Watch, either, because the improvements won’t feel significant. But if you bought the original Apple Watch in 2015 and liked it, this will be a great upgrade. The first watch was sluggish, with limited battery life, and it no longer receives operating system updates. The Series 4 addresses all of the first-generation watch’s flaws, and the speed boost will be a big step up.

Hypochondriacs, beware

If you are simply a health-conscious person, should you get the new watch? I wasn’t able to test the EKG app because it is not out yet. Those with heart conditions would be wise to wait until Apple releases its electrocardiogram app this year to see if the technology works well.

It is also important to not regard the watch as a catchall device for health monitoring. Dr. Weiss said that even if the EKG app detected arrhythmia in a young person, for example, that information would not necessarily be useful because the condition might not cause a problem at a young age. Instead, it may just induce anxiety.

“What it is going to do is make you aware of having this condition, which could impact your insurance, which could impact your mental state and your state of happiness,” Dr. Weiss said.

There is one demographic that may be more interested in the watch for health reasons: the elderly. Apart from the electrical heart sensor, the new watch can detect when its owner has taken a nasty fall. The feature is turned on by default for people 65 and older (based on the birth date they entered into the watch’s software), and the watch will automatically call emergency services and send a message to your emergency contact if you remain immobile for a minute after a fall.

I struggled to trigger the fall detector. In the name of journalism, I took several dives at home onto my mattress, a couch and a dog bed to try to get it to work.

I also headed to a rock climbing gym, where I climbed up six walls and fell onto a padded mattress onto my side and onto my back. No dice. Last, I clambered atop the gym’s tallest wall — about 17 feet high — and dropped down. When I landed, the watch vibrated and chirped. Alas, it was only a notification alerting me that someone had liked a photo on my dog’s Instagram account.

My failure to trigger the fall detector was not necessarily a bad thing. To design the feature, Apple worked with people in assisted living facilities and movement disorder clinics to collect data about real slips and falls — not my phony ones.

As for my own health, the new Apple Watch basically showed me I was getting plenty of exercise. And for those who were wondering: Dr. Weiss pronounced that the heart activity from my EKG was normal.