Apple Watch Series 3 GPS 42mm vs 38mm difference – how to sync it?


What is good in Apple Watch Series 3? It comes with Dual-core S3 processor, GLONASS, Galileo, and QZSS, Barometric altimeter, Optical heart sensor, Accelerometer and gyroscope, Ion-X strengthened glass, Composite back and many more benefits.  If you get the gps+cellular, you do not need to have the watch activated with cellular service. If you don’t have the gps+cellular watch activated with cellular service, it works just like a gps only watch.  Which is worth buying – Apple Watch Series 3 GPS 42mm vs 38mm?

We independently review everything we recommend. When you buy through our links, we may earn a commission. Lean how we earn commission

Pros & Cons – Apple Watch Series 3


  • Good smartwatch battery life
  • Great, solid design
  • Clear, bright screen
  • Fantastic fitness features
  • Amazing value for money
  • Super smooth performance and navigation
  • Easy-to-use UI


  • Siri still patchy
  • High price for 4G model
  • No always-on display option
  • Battery life just under two days
  • Won’t track sleep natively
  • Only iPhone compatible


Phone OS Compatibility iOS
Watch OS watchOS
Processor Apple S3
Display Size 1.65 inches
Display Type OLED
Fitness Features Accelerometer, GPS, Heart Rate Monitor
Estimated Battery Life 18 hours; 5 hours with GPS
Separate App Store Yes
Phone Call Capacity Yes

Price – Apple Watch Series 3 GPS 42mm vs 38mm

  • Launched September 22 2017, still on sale from Apple
  • Price starts at £199 / $199 / AU$319
  • LTE version starts at £299 / $299 / AU$469

At launch in late 2017, the Apple Watch 3 was the most expensive wearable the company sold but now the price has shrunk since the launch of the Apple Watch Series 4 and Apple Watch 5. It’s still not an inherently cheap smartwatch, but it’s a lot more affordable now.

The former costs £299 / $299 / AU$469 / AED 1,199 or £329 / $329 / AU$519 / AED 1,329 (for the 38mm and 42mm bands respectively) these days thanks to a serious discount after the release of the Apple Watch 5.

The 3 series GPS version is much cheaper at £199 / $199 / AU$319 for the 38mm and £229 / $229 / AU$369 for the 42mm.

What is the key difference – Apple Watch Series 3 GPS 42mm vs 38mm

Apple Watch Series 3 GPS 38mm fits under long sleeves better than the 42 would have especially if you wear tailored button downs. I am on the newest beta and have been going 14 hours a day and ending with over 80% battery so the larger battery is a non issue. I have the same sized wrists. I went with 38 because it was more comfortable, the way the strap wrapped had less pressure points.

Comparison – Apple Watch Series 3 GPS 42mm vs 38mm

ModelApple Watch Series 3 38mmApple Watch Series 3 42mm
Resolution272 x 340 pixels312 x 390 pixels
Total Display Area563 sq mm740 sq mm
Sport Band Size (S/M)130-180mm140-185mm
Sport Band Size (M/L)150-200mm160-210mm
Weight (Aluminum, GPS only)26.7g32.3g
Weight (Aluminum, GPS + Cellular)28.7g34.9g
Weight (White Ceramic)40.1g46.4g
Weight (Stainless Steel)42.4g52.8g
Battery Life18 hoursUp to 20-25% longer

Wrist cover

Apple Watch 3 Series has below wrist circumference –

Apple Watch Series 3 GPS 42mm vs 38mm difference


Both version offer retina resolutions, but the 42mm packs more pixels with 312 x 390 pixels as compared to the 272 x 340 resolution of the 38mm model. If you want a bigger display and more pixels, then you should purchase the 42mm model.

Display Size

Besides physical size, one other difference between the 38,, and the 42mm Watch is the size and resolution of the device’s display. According to Yahoo’s David Pogue, the 38mm Watch will include a 1.5-inch display while the larger 42mm version ships with a 1.7-inch.

Watch band feature – Apple Watch Series 3 GPS 42mm vs 38mm

42mm Watch bands

  • Leather Loop with Magnetic Closure (Bright Blue Leather, Light Brown Leather, or Stone Leather)
  • Fluoroelastomer with 18-Karat Yellow Gold Pin (Black)
  • Classic Buckle with 18-Karat Yellow Gold Buckle (Midnight Blue Leather)

38mm Watch bands

  • Modern Buckle with Stainless Steel Buckle (Soft Pink Leather, Midnight Blue Leather or Brown Leather)
  • Modern Buckle with 18-Karat Rose Gold Buckle (Rose Gray Leather)
  • Modern Buckle with 18-Karat Yellow Gold Buckle (Bright Red Leather)

Apps compatibility

Many Apple Watch apps were also designed for the 42mm version, and you’ll notice the resizing in the form of clipped and hyphenated words so that the text can fit in the 38mm. However, keep in mind that you won’t be interacting with your smartwatch as much as your phone. It’s mostly a secondary gadget for fitness information and app notifications.

Battery life – Apple Watch Series 3 GPS 42mm vs 38mm

Battery capacity is higher for 42mm models than for 38mm models.

For example, for Apple Watch Series 3 (GPS + Cellular) models:

  • 38mm: 1.07Whr
  • 42mm: 1.34Whr

Battery life varies depending on use and other factors.

The 42mm version comes with a battery that’s roughly 20 to 25% bigger than the 38mm version. But what does that mean in terms of practical usage?

Extensive testing showed that the bigger battery does last 20 to 25% longer than the smaller one. This is even more important if you’re planning to use the cellular capabilities of the LTE-enabled Apple Watch all day. If you want to be able to leave your iPhone at home and just have a wearable on while running or working out, a bigger battery will give you more peace of mind.

Apple Watch Series 3 GPS 42mm vs 38mm review


When it comes to colour options, the Apple Watch Series 3 is only available with a silver or grey aluminium case although there are hundreds of different strap designs available


The Series 3 is slightly thicker chassis than the ones you’ll find in today’s Apple Watches, measuring 11.4mm thick. Comparably, the Apple Watch Series 6 measures a whole millimetre slimmer at just 10.4 mm. The Series 3 is also a little heavier, weighing 52.8g as opposed to the 47.1g weight of the Series 6. 


The Series 3’s 1.65-inch OLED screen, which is nice and easy on the eye thanks to it offering some stunningly rich colours and deep blacks. If you want us to get down to the display’s nitty-gritty, we can tell you that the Series 3’s 42mm variant has a 312×390 resolution display, whereas the 38mm edition boasts 272×340 pixels. 


this is the same Apple Watch, with a decent 1,000 nit display, as rich as it’s ever been. The display is not noticeably brighter or sharper on the newer Series 4 or Series 5, despite the pixel density improving.


The Series 3 smartwatch comes with Apple’s S3 chipset that sports a dual-core 64bit processor and GPU. While it’s not going to quit as nippy as the Series 5 or 6, for instance, it’s still able to perform all the tasks you need it to with ease.


The Apple Watch 3 can now also be upgraded to watchOS 6 too, so you can make use of a lot of new software features, including an App Store on your wrist. That followed on from an update to watchOS 5, which added the likes of Siri Shortcuts and a Walkie-Talkie feature.

Storage & Syncing

One of the best things about the Apple Watch 3 is that it’s got 16GB internal storage (for the LTE version, 8GB with just GPS), which means you can fill it with your tracks from your phone.

The Watch 3 will naturally sync tracks that you play regularly from the phone, which is nice when you fancy listening to some music and haven’t bothered to sync anything over recently (or don’t have the LTE version of the Watch or a data connection for streaming).

Swim tracking

The Apple Watch 3 follows in the footsteps of the 2 by allowing you to get the thing wet and dunk it in the water to track your swims. It’s 5ATM resistant, so you’ll be able to thrash around in the pool with it – and it’s a decent device to do so with.

HIIT workouts

The Apple Watch 3 also packs other fitness capabilities now – namely the ability to track your high intensity interval training (HIIT) workouts. 

This doesn’t really differ much from the ‘other’ workout option that was there before, except the calorie burn is going to be more accurate.

It’s nice to have this different mode – for nothing else, to be able to see what you’ve done in a workout –  but it’s mostly just for a calorie burn.

Fitness app

A newly announced partnership means that Strava works with Apple Healthkit, so you can use the Workout app and still get your Segments data – the best of both worlds. There’s also a decent third-party Strava app too, which shows how versatile the Apple Watch can be.

Heart rate

Apple is tackling heart rate in two ways on the Watch Series 3. The first is still heavily geared towards fitness and giving you a better measurement of workout intensity, and now it can also measure resting heart rate throughout the day. That’s a valuable piece of data because it’s a strong indicator of your current state of health. A lower resting heart rate is definitely a good thing, in case you were wondering.

4G connectivity 

The stand-out feature of the Watch Series 3 at launch was its 4G connectivity in the GPS+Cellular version, enabling you to ditch your iPhone completely should you wish to go for a run without it. There’s a full 4G LTE and UMTS cellular radio antenna hidden in the display, which kicks into action the moment you step away from your iPhone. 

Bluetooth & Call quality

The watch’s call quality is comparable to that of my iPhone, and when it’s paired with Apple’s AirPods, talking on the watch is effortless. You will definitely look like you’re talking to yourself without a phone in hand, but if you don’t care about looking slightly awkward in public, then proceed.


You’re getting two things with the new Apple Music streaming capabilities: Apple Music directly, and Beats Radio. These are both accessed the most simply through Siri – you can tap through the Watch to get there, but it’s very fiddly.

It’s not perfect – especially when outside and walking or running – but when it works it’s a dream, a futuristic scenario where you command almost any song in the world via a chat with your wrist.

The easiest way is to ask Siri on the go to play the kind of music you want – whether that’s by genre, a playlist you’ve already created but not synchronized, or just a certain song. 

Alternate – Apple Watch Series 3 GPS 42mm vs 38mm

I still really like Fitbit’s total package of nutrition, sleep tracking and social goals. Apple doesn’t quite do the same thing for Apple Watch. The added barometer and improved heart-rate graphs are welcome adds, but the Apple Watch battery life trails most Fitbits, which get four days or even longer. But at least the Apple Watch can be worn swimming. The forthcoming Fitbit Ionic has added swimproofing, too, and mobile payments and apps, but its onboard music and smartwatch functions feel far, far inferior to those on the Apple Watch. Apple Watch is the superior smartwatch. Fitbit generally wins for more casual use.

Editor’s recommendations

Lead Content Editor
Lead Content Editor

I enjoy creating stuff and giving back to my community. My days are spent producing content for brands who need an internet presence and for things that I adore. I bring with me six years of experience generating content and obtaining leads from untapped markets. I concentrate on the qualities and advantages of the goods that add value for my audience. After reading my reviews, anyone who want to purchase a product from me are given my honest and open recommendation. I integrate my reviews with those of actual people to make the content authentic and accurate. Please take a moment to contact me if you see any deviations; I always value and appreciate hearing from my readers.

Articles: 1393