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Apple Watch Series 4 review: Best for iPhone owners, but not the best smartwatch

Written by Matthew Miller, Contributor
Apple Watch

Apple Watch Series 4 (GPS) - space gray aluminum - smart watch with sport loop - black - 16 GB

8.7 / 5

pros and cons

  • Expanded viewable area
  • Light weight
  • Solid battery life
  • Gorgeous display with stunning animations for watch faces
  • No advanced sleep tracking
  • No always-on display option
  • No support for third party watch faces
  • Swipe to switch watch faces is annoying
  • Editors' review
  • Specs

The new Apple Watch Series 4 is available today and this new wearable from Apple may have been the best new product launched at the event and couple of weeks ago in California. The Apple Watch Series 4 has been "redesigned and reengineered" with a focus on the features that people use the most: health and wellness.

A couple of months ago I sold my Apple Watch Series 3 because I was primarily using Android phones and other wearables, such as the Garmin Fenix 5 Plus, were better serving my needs. After watching the Apple announcement for the Series 4 watch I ordered one the minute they were available because the larger display, focus on health and wellness, longer battery life, and ability to still use all of my existing 42mm Apple Watch bands was appealing.

I picked up an Apple Watch Series 4 at the Apple Store and am tested it with an Apple iPhone X and iPhone XS Max. I selected the non-LTE model since I only used the last generation with LTE for a total of about 30 minutes over the cellular network in a year of use. At $10 a month, the cost to use the LTE model was ridiculous and not worth the added cost.

Also: Why I'm buying an Apple Watch Series 4 TechRepublic


The packaging of the Apple Watch Series 4 is interesting this year with an origami style approach where you unfold a few layers to then find the Apple Watch body secured with no band attached in a microfiber softshell. The straps are located in another area with the charger buried deep inside. Many images of colorful watch band and watches are inside the packaging and it is a bit of an experience just to unbox it. There's a photo of the box in the image gallery.

One of the first things I noticed on the Series 4 is the thickness of the Apple Watch. It is now 10.7 mm, compared to 11.4 mm on the Series 3. That's not much, but enough to notice when you mount it on your wrist. It also has a different optical heart rate sensor configuration with a ceramic ring on the back that is designed to help with the ECG app functionality coming later this year.

The digital crown has been modified to now include haptic feedback. The digital crown is also used to help complete a circuit in your body for the ECG measurement. Because the ECG functionality will be coming later, it was not tested in this review.

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The accelerometer has been improved to measure twice the level of gravitational forces and is part of the new fall detection and notification system.

I purchased the 44mm model which has a 368x448 pixels display and 977 square mm of display area. This is 230 square mm more of display area compared to the 42mm Series 3.

The general squircle form factor, watch band system, and button layout is the same as before. Thankfully, even though the larger model is now 44mm, the watch bands for the 42mm Series 3 are still compatible with this slightly larger Series 4.

Also: We take the Apple Watch Series 4 for a spin CNET

Specifications of the Apple Watch Series 4 include:

  • Processor: Apple dual-core 64-bit S4
  • Display: 1.78 inch, LTPS OLED Retina 448x368 pixels resolution
  • Operating system: WatchOS 5
  • Storage: 16 GB internal storage
  • Wireless technology: NFC, 802.11 b/g/n WiFi, Bluetooth 5.0, and GPS/Glonass/Galileo. LTE is available on select models too.
  • Sensors: 32 g-force accelerometer, barometer, gyro, ECG electrode, optical heart rate, ambient light
  • Other features: IP68 and 5 ATM dust and water resistant, integrated microphone and speaker
  • Battery: Up to 18 hours of advertised battery life
  • Dimensions: 40 and 44mm models. Large one measures 44 x 38 x 10.7 mm and weighs 48 grams

Watch software

The Apple Watch Series 4 launches with watchOS 5 and at first glance not much has changed. However, I spent a little time with it to discover:

  • Raise to launch Siri without having to say "Hey Siri"
  • Podcasts can now be enjoyed while you workout with no iPhone
  • Automatic workout detection
  • Grouped notifications
  • View web content
  • Schedule do not disturb, including a location-based option

Apple is intelligently using the sensor in the watch to make it a great option for those who are mobility-challenged. Automatic fall detection can be set up to trigger a text and emergency call if the watch detects an actual fall. The Apple Watch will vibrate and emit progressively louder sounds until one minute of inactivity goes by. Without any acknowledgement, it will then send a text message to your emergency contact with your last recorded location.

The ECG function is not yet available, but eventually the Apple Watch will help detect possible anomalies that could inform doctors and lead to more detailed and comprehensive tracking and diagnosis. Check out Jason Perlow's story on how the Apple Watch saved his life.

Apple Watch Series 4 review: in pictures

You can set warnings for low and high heart rate detection, but they don't work for everyone. The lowest low heart rate warning is 40 bpm and if your heart rate is at this level for more than 10 minutes then a warning appears. My resting heart rate is usually down in the low 40s so this low heart rate level should be another 5 bpm or more lower since my heart rate will drop in the 30s while sleeping.

Samsung has had automatic detection of activities on its watches since at least the Gear S3 and I found it handy for my one mile walk to and from the train. I tested this for the last week on the Apple Watch 4 and as long as my walk was at a fast pace detection kicked in after six minutes oro so and then prompted me with app up to save it as a workout.

Watch faces with up to eight complications are now available and I've been enjoying the infograph modular face that provides a ton of information with a simple glance.

There is a new Walkie Talkie feature in WatchOS 5 that works through FaceTime audio. Your contacts need to also have Apple Watches in order to use this feature as it does not work from an Apple Watch to an iPhone or back the other direction. Kevin Tofel and I tested this out several times over the past week using my Apple Watch 4 communicating with his Series 3 Apple Watch. The audio was clear and crisp with transmission and acceptance happening faster than we have seen via voice memos and text messaging.

To be more useful, the app needs to automate some of the available-for-appointment times, locations, and such. It will show you as unavailable when Do Not Disturb or Theater mode is active.

On the other hand, I don't quite get the fascination or need for automatic detection for other activities, unless you simply forget to start your workout often. I never forget to start tracking my runs and bike rides on my wearables because I am making sure I have the appropriate app launched, a GPS signal is secured, and my heart rate monitor is tracking. The automatic tracking of runs doesn't make sense to me and locks you into Apple Workouts, which then cannot be synced to Strava, Runkeeper, or other services.

There are plenty of apps specific to running and other types of workouts and these commonly have more advanced settings for the displays you see and whether that information can be shared outside of the Apple ecosystem. Using these apps will still have an effect on your Apple Workout rings so use the app that is best for you.

Also: Kardia EKG after Apple Watch: AliveCor's future of remote patient care

I went running with the Apple Watch, Galaxy Watch, and a Garmin Fenix 5 Plus. The Apple Watch matched the Garmin very closely, within 1/10th of a mile over 3 miles while the Galaxy Watch's GPS jumped off the route a bit while running through some tree-covered streets. The Apple Workout app provides some custom options for data that appears on the display while running, but with the Galaxy Watch and Garmin Fenix 5 you can add multiple screens and customize the data fields more extensively. For casual runners, the Apple Watch is fine and the accuracy is solid.

Some advanced features we see on other wearables that are not yet present on the Apple Watch include advanced sleep tracking with REM, deep, and light sleep periods, and stress tracking and management. I don't think Apple will officially launch sleep tracking as a feature until it can achieve another day of battery life. There are third party sleep tracking apps, but they do not use HRV to track REM stages and only give you fairly basic sleep stats.

iPhone software

One aspect of the Apple Watch experience that I find valuable is the ability to fully set up and manage the Apple Watch right from your iPhone. You can set up watch faces with complications, install and remove apps, manage the app launcher appearance, and more. I have most of what I want on the Infograph Modular watch face, but can't get the Strava complication to appear yet for some reason.

Other iPhone apps that connect and work directly with the Apple Watch include Apple Health and Activity. Activity shows your colored rings and the details that go into making those rings work. If I could just get the ability to sync to other services, like Strava, or export my GPS data then I would likely use Activity and Workout as the primary Apple Watch fitness apps.

I primarily use the Apple Watch for run tracking and if you open the Workout utility in the Apple Watch iPhone app, you can select to view multiple metrics and then choose to have up to five metrics shown on the Apple Watch as you run. It is not as customizable as a GPS sports watch, but it is better than most smartwatches today.


If you use an Android smartphone, there is no need to even read this review since the Apple Watch only works with iOS. However, you can use a Galaxy Watch or Google Wear OS watch with an iPhone. The Galaxy Watch is a fantastic option that provides advanced sleep tracking, stress tracking, Spotify support, ability to play music through the speaker of the watch, and more at a lower price. It does not have some of the more advanced medical features coming later to the Apple Watch Series 4, but is a great choice at $329.

There is no current Google Wear OS device I would recommend and until we see the next version of Wear OS launch, possibly at a Google event in a couple of weeks, there is nothing to consider at the moment.

There are many advanced GPS sports watches and fitness trackers that serves as very fine wearables, but none offer the full smartwatch functionality seen in a Galaxy Watch or Apple Watch.

Price and availability

Apple again has aluminum and stainless steel models, but since I like to use the Apple Watch for exercise the lighter aluminum casing ($399 starting price for 40mm) is preferred. The stainless steel models start at $300 more ($699) than the aluminum models, which is a significant increase. It is $30 more for the 44mm model.

Interestingly, the stainless steel models only come with the cellular option. For $100 additional cost, you can buy an aluminum model with cellular capability, but there are no WiFi-only stainless steel models.

The Apple Watch Series 4 is available now at Apple, Best Buy, and various other retailers with a host of available bands ranging from $49 to $489.

Daily usage experiences and conclusions

The expanded display on the Apple Watch and slightly thinner casing are both wonderful and obvious improvements to a great smartwatch. In the past, I would say if you had an iPhone then there is no smartwatch better than the Apple Watch. However, with the increased price ($70 more than last year's Apple Watch 3 to start) and stiff competition from Samsung, the Galaxy Watch (now available in a smaller size too) is a compelling option for iPhone users too.

I purchased this Apple Watch Series 4 on launch day, but am likely going to return it and stick with the Galaxy Watch as a smartwatch and my Garmin Fenix 5 Plus for serious activity tracking. Samsung Health is a full featured system for health and fitness tracking that I find much better than Apple's cryptic Health platform.

The Apple Watch Series 3 I had included LTE, but after using it for about 30 minutes over the past year I could never justify the $10+ monthly fee again. It's not the minor additional cost, but the principle that I have to pay such a fee for a service that is rarely used. LTE is a great safety net, but I'm not committed to paying the fee and an additional $100 for a watch that supports LTE.

Apple's new Watch Series 4 is a nice improvement over previous generations and current Apple Watch fans are certain to be very happy with this new model. Those thinking of a first smartwatch have a couple of good options.

How to use Apple Pencil: 21 features, tips, and tricks

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