By Joanna Stern | Photography by Kenny Wassus/The Wall Street Journal 

There is only one thing I'd urge you to wear this year: a mask. Oh, and pants. Please wear pants -- even on video calls.

And what about the brand new $399 Apple Watch Series 6? Nope.

Hold up. Shouldn't this be the year I encourage you to put cutting-edge health tech on your wrist? Wearables are now doing everything from scanning for early signs of infection to detecting heart problems to automatically calling emergency services if you fall.

Sure, the top-of-the-line Apple Watch Series 6 can do that stuff but so can models that cost far less.

If you have already got a two- or three-year-old Apple Watch, the gains with this new model aren't substantial. Same screen, same battery life, same core functionality. And I found this year's standout health feature -- a blood-oxygen sensor -- not ready for prime time, not to mention not useful.

Plus, if you're a first timer, or in need of an upgrade, Apple now has two other lower-cost options: the Apple Watch SE and Series 3. Actually, make that three: The best deal going right now might be a refurbished Series 5.

It is OK to be confused. I'm here for you. After testing all the models last week -- along with the $330 Fitbit Sense -- I have arrived at a new theory of Watch-Nomics: You should upgrade your Apple Watch every three to five years. Any sooner, and spending more on a watch doesn't mean proportionally more features. So make the call on your needed features, then make a purchase.

The Choices

Remember your SAT multiple-choice tactics? Eliminate two choices and you suddenly have a 50/50 shot at a correct pick. Buying an Apple Watch is like that:

A) Apple Watch Series 6 ($399): This one has the larger screen introduced in 2018, with an always-on display showing the time. It now has a slightly faster processor, slightly faster charging and the full health package, including an ECG electrical heart-rate sensor and new blood-oxygen sensor.

B) Refurbished Apple Watch Series 5 ($329): It's basically a Series 6 without the blood-oxygen sensor. Apple stopped marketing it, but at time of publication, you could still find some variations in its refurbished store.

C) Apple Watch Series SE ($279): This resembles a Series 5 or 6, but without the always-on display, ECG or blood-oxygen sensor. It still has heart-rate tracking and notifications for high, low and irregular heart rate, as well as fall detection.

D) Apple Watch Series 3 ($199): OK, almost there. This one has an older design with a smaller screen, slightly shorter battery life and slower performance. It also has heart-rate tracking and heart-rate notifications, but no fall detection.

The Features

I anticipate most will choose A or C, especially if Apple runs out of refurbished Series 5s. So the real question is this: Are a blood-oxygen sensor, an ECG and an always-on display worth $120?

When I got the blood-oxygen sensor to work, most of my readings were in the healthy high-90% range. During a visit to my doctor, the watch even compared point for point with a medical-grade vital-signs monitor. However, often when I would manually initiate the 15-second test, I would get an "Unsuccessful Measurement," indicating that the test didn't work. Sometimes I would get a lower reading, like 94% -- even when my trusty $45 Walgreen's pulse oximeter said 99%.

The little disco ball of green and red lights on the back of the watch needs to be steady, flush and tight against the skin to get a reading. The new, wonderfully comfortable Solo Loop straps help with that, but apparently mine was a bit too loose. Sliding the watch up my wrist a bit more has improved this. Still, using this is far too unreliable and inaccurate -- even if Apple doesn't suggest this for medical use.

An Apple spokesman provided this statement: "The Blood Oxygen feature has been rigorously tested across a wide spectrum of users and across all skin tones. For a small percentage of users, various factors may make it difficult to get a blood oxygen measurement including motion, watch placement on the wrist, skin temperature and skin perfusion."

But even if this all worked, there isn't a clear enough reason for me to need this on my wrist all the time. Why shouldn't I just pull out a pulse oximeter if I'm worried? While a low blood-oxygen level can be a gauge for the severity of Covid-19 and other conditions, there is no Apple Watch alert if yours drops below a certain threshold.

Apple says this is a wellness and fitness feature, not a health one, and it is beneficial to those who travel to places with higher altitudes or who are involved in performance training. Also, much like the heart-rate sensor, which is proving to be central to Covid-19 wearable studies, the blood-oxygen sensor can now be used to collect data to build detection algorithms and further medical research.

As for the always-on display, while I do appreciate being able to glance down and see the time without tapping on my wrist, I have had it disabled on my Series 5 for most of the year to eke out a bit more battery life. I'm even more interested in saving battery now that sleep tracking arrived with WatchOS 7.

No matter which model you pick, you have to recharge every day or so. If you sleep with your watch, you have to charge it when you wake up. Compare that to the $330 Fitbit Sense, which I charge every five days or so. It keeps tabs on your temperature, blood oxygen and heart rate. That said, it lacks a lot of the non-health functionality of the Apple Watch, and Fitbit's software can be slow and buggy.

The ECG is really the only feature I would consider for the extra money. You have to follow your heart on that one (sorry, had to.) It's a shame Apple pulled a vital health feature from the former Series 4 or 5 model it's now calling SE.

The Future

Rewind the clock to 5 1/2 years ago to when the Apple Watch first shipped, and the technical leaps are massive -- waterproofing, bigger screens, better battery life, advanced sensors. Alongside those leaps, the product found its central purpose: fitness and health.

But it was mostly there with the Series 4. So why has development slowed to a snail's pace since then? There could be two reasons: Apple engineers haven't quite gotten the next major improvements right (multiday battery life in a thinner package), and Apple realized no one wants to buy a watch every two years like a smartphone. It makes you wonder why we need yearly updates on these at all?

Big leaps are still coming. I had a vision of it when I was hooked up to that monitor at my doctor's office. The Series 6 already does two of the four readings: pulse and blood-oxygen levels. Temperature and blood pressure? Not yet. By combining more advanced health sensors and software that detects fluctuations, the Apple Watch and other wearables are going to become our ever-present health care minders.

In the here and now, though, the answer isn't to buy a new one whenever a sensor gets added -- especially when it doesn't necessarily work. If you have an older model, grab a pulse oximeter from your drugstore and the super comfy $49 Solo Loop band from an Apple Store and call it a day. If it ain't broke, don't Series 6 it.

-- For more WSJ Technology analysis, reviews, advice and headlines, sign up for our weekly newsletter.

Write to Joanna Stern at joanna.stern@wsj.com

 

(END) Dow Jones Newswires

September 24, 2020 09:14 ET (13:14 GMT)

Copyright (c) 2020 Dow Jones & Company, Inc.
Apple (NASDAQ:AAPL)
Historical Stock Chart
From Sep 2020 to Oct 2020 Click Here for more Apple Charts.
Apple (NASDAQ:AAPL)
Historical Stock Chart
From Oct 2019 to Oct 2020 Click Here for more Apple Charts.