The History Of Apple Watch: How The Best-Selling Smartwatch Has Evolved Over Time

By the time the first Apple Watch was released in 2015, other tech giants like Sony, Microsoft, and Samsung were established players in the smartwatch market. But Apple, as it tends to do, quickly made its mark.

The Apple Watch combines fitness tracking, health monitoring, and communication tools in a sleek device that is only compatible with the iPhone. Nearly a decade later, Apple has consistently refined its features, and each new release addresses any shortcomings. Today's models can even save your life in an emergency with features like fall detection or blood oxygen measurement, so it's as practical as it is stylish.

Therefore, it's no surprise Apple has displaced top watch brands to become the most successful globally, making up 21.6% of the smartwatch market as of 2024. Here's a look at the history of the Apple Watch and how it has evolved to become the best-selling smartwatch in the world.

Like many first-gen products, Apple's first watch, popularly known as the Series 0, definitely had some room for improvement. Still, it was enough to place the Apple Watch ahead of competitors. In the second quarter of 2015, the year it was released, the company shipped out 4.2 million units of the Apple Watch, beating brands like Xiaomi to become the world's leading vendor of smartwatches.

On first impression, the Series 0 was stylish, with an excellent design and great finish. Two size options were available: a 38mm and a 42mm. But the watch's battery could only last for a day, not much more. There were also some issues with the integration of third-party apps, most of which didn't sync so well with the watch or took a while to load.

Apple offered three models with this generation of the Apple Watch. The first was the Sports model, which was the base version. Made with aluminum, it was priced starting at $349. Next was the steel version, which cost $549. The Edition model stood out at a significantly higher price point, costing a whopping $10,000 for the 38mm and $12,000 for the 42mm watch.

September of 2016 saw the release of two Apple Watches: The Series 1 and Series 2. Both gadgets were released along with the iPhone 7, 7 Plus, and the first generation of the AirPods.

The Series 1 looked almost identical to the first Apple Watch, but it addressed some of its issues, most notably the price point. The 38mm had a starting price of $269, while the 42mm started at $299, significantly lower than their predecessor.

The main update, tech-wise, was an S1P dual-core processor, which improved the watch's performance. However, the watch was only offered in the Sports model, limiting the design options available to buyers. With water resistance not much changed, the Series 1 also has an IPX7 rating, meaning it can last 30 minutes at one meter deep in water. But while it's okay to shower with it on, taking it for a swim is not advisable.

The Series 2 didn't change much in terms of design, adopting the features of the Series 1. However, it did offer more options. It was available in stainless steel, aluminum, and a newly added ceramic edition. But looks weren't its biggest selling point.

The Series 2 had a GPS function for fitness tracking, which you couldn't find on the Series 1. However, while this feature meant you could track your run, it put more strain on the battery. The battery itself remained largely unchanged from the Series 1.

Waterproofing was another selling point for this watch. The Series 2 came with 50-meter water resistance so that you could wear it for a swim. Display brightness also went up, with a 1000-nits display, but it still lacked what many users clamored for — an always-on display. The difference in features placed the Series 2 at a significantly higher price than the Series 1, starting at $369. At this point, Apple discontinued the ridiculously priced Edition Watch that came with the first generation.

The Apple Watch Series 3 retained the GPS chip, display resolution, and water resistance of the Series 2. However, the most notable introduction was its Series 3 LTE version, which provided built-in cellular data support. While not new to smartwatches, this was a novel addition to the Apple Watch.

With LTE connectivity, you could stay connected to their smartwatches without having your smartphones around — or at least, that was the goal. In practice, this feature could have worked better. Some users reported that the smartwatch was slow to switch to LTE when out of range of their phones. Apple later acknowledged this bug and released a software update to address it.

This generation also kept the same design as the previous watches but had all-around upgrades, like improved battery life and 16 GB storage space, double that of earlier models. In addition, there was a significant 70% boost in speed and performance thanks to its faster processor. The LTE version of the Series 3 was priced starting at $399, while the non-LTE version cost $329.

The next Apple smartwatch was the Series 4, released in September 2018. For the first time, Apple made significant design changes to the watch. Specifically, this watch had a 30% larger screen, with increased pixel density and a 1,000-nits display. For the first time, it was offered in two new case sizes: 40mm and 44mm. The watch became thinner, so this increase in size didn't make it feel bulkier. Also, the bands on older models remained compatible with the Series 4 despite the difference in size. Less noticeable was the rear of the device, which was now built with ceramic instead of the metal hardware on previous models.

As for the performance and software, the Series 4 came with a faster processor and was ultimately easier and smoother to use than the Series 3. The software also appeared to perform better at heart rate monitoring and was generally more tuned to health detection and not just fitness tracking.

The Series 4 also had an optional LTE version, which this time did not suffer the problems of the Series 3. The standard model had a starting price of $399, and the LTE model started at $499.

The Apple Watch Series 5 shared a lot of features with the Series 4, coming with the same bigger display and being available in 40mm and 44mm. Ceramic and titanium case options were added. Beyond that, Apple improved the options to customize the look of the watch. Before the Series 5, the Apple Watch came with a default strap, and a different one had to be purchased separately. But now, buyers could choose a strap they liked when purchasing.

Apart from this, there were only a few updates to the watch. The storage went from 16 GB to 32 GB, but what really stood out was the newly introduced always-on display. This feature was a welcome development that users had clamored about for years. When enabled, if you're not actively using the watch, it would stay on, but in a low-display mode, intended to conserve battery life.

However, there was no actual improvement to the battery life as Apple promised the same 18 hours as it did on previous models. Nonetheless, the Series 5 had the same $399 starting price point as the Series 4.

During the Covid-19 pandemic, Apple introduced three new smartwatches, including its well-anticipated flagship watch, the Series 6. The gadget came with new health and wellness features, including the optical blood oxygen sensor. For the first time, Apple introduced sleep tracking and hand-wash tracking, which was subsequently made available for older models.

Design-wise, the Series 6 remained roughly the same. New blue and red aluminum case color options were added. Users could still customize their watch strap, but Apple added the Solo Loop, a buckless band made with stretchy silicone. This was made available in seven different colors, and there was also a braided Solo loop for a more sophisticated look.

Apple also introduced a number of new watch faces, including the Chronograph PRO, GMT, Memoji, typography, and Stripes Faces. Each face had different unique styles and functions. For instance, the GMT showed two different time zones, while the Memoji Face displayed Memoji characters created by the user.

As part of the 2020 launch, Apple released the SE smartwatch for the first time. The Apple Watch SE, just like the iPhone SE, was an affordable version of the company's flagship watch, starting at $279 upon its release. For comparison, the standard version of the Series 6, which launched at the same time, was set at $399.

Essentially, the SE wasn't far off from the Apple Watch Series 4. It did not come with the always-on display introduced on the Series 5. Also missing were the blood oxygen monitoring and electrocardiogram sensors that the Series 6 was equipped with. While it missed some wellness features, it retained a heart rate sensor, meaning you could still get heart rate measurements and notifications.

There were several notable design differences compared to the Series 6. The SE only came in an aluminum build and three color options: silver, gold, and space gray. This was unlike the Series 6, which was made available in a wide range of case materials and colors. However, the SE had the new and braided Solo Loop. Overall, while the Apple Watch SE fell behind the Series 6 in terms of features, it was still a great option, and users still got a faster processor than older models.

The Series 7 didn't have major upgrades. Apple added a bigger screen display by reducing the size of the bezels. As such, the watch was now offered in 41mm and 45mm sizes. But, the design was still basically the same as that of Series 6. This was contrary to the rumors at the time that the watch was getting a major redesign.

New color options were, however, included, featuring starlight (a blend of gold and silver), dark green, and midnight colors. The blue and red colors that were previously available were given a refresh for the new generation. In addition, Apple improved the watch's durability, making the front crystal cover much thicker and more resistant to the elements.

The newly introduced bigger screen display now allowed users access to a miniature but full QWERTY keyboard. This enabled tap typing or swipe typing through QuickPath. There were also two added watch faces: the Modular Duo and Contour. Stuff like the health sensors and battery life remained the same. However, charging became faster, as the watch now had a redesigned charging puck. It used a USB-C, which, according to Apple, makes it charge 33% faster than the Series 6.

The Series 8 was one of the three watches Apple released in 2022 and the most anticipated. Rumors had suggested that users would get a number of new features, like a temperature sensor, blood sugar level detector, satellite connectivity, and crash detection. Apple did deliver on a few of these, but some, like satellite connectivity and blood sugar level detection, were left out.

Still, the new add-ons were a significant improvement for the Apple Watch. The introduced low-power mode meant the watch could now last up to 36 hours without charge, much higher than the default 18-hour battery life. There was also the crash detection feature, also made available on the newly released iPhone 14. This technology uses advanced sensor-fusion algorithms and an enhanced gyroscope. Paying attention to motion, pressure, and sound, the device detects when a crash has occurred and will alert an emergency service.

The final highlight was the skin temperature sensor, which boosted the watch's already impressive fitness tracking abilities. It not only improved sleep tracking and cycle tracking but also helped track ovulation, illnesses, and other health information.

The second generation of the SE smartwatch was introduced in 2022. Like its predecessor, it offered most of the core features available on the Apple Watch but at a cheaper price, proving once again that you don't need to spend so much for a quality smartwatch experience.

Design-wise and even in terms of features, the SE shared more similarities with the first gen than the Series 8. It came in 40mm and 44mm size cases, as opposed to the Series 8, which was available in 41mm and 45mm. For the fitness sensors, the SE also didn't get some newer updates like skin temperature and blood oxygen. However, a major noticeable difference from the original SE was the increase in processor speed. The second-gen adopted the more modern S8 SiP processor, like the Series 8, giving it a faster and smoother experience. There were also two new colors and some changes to the hardware.

So, overall, there wasn't much difference compared to the original SE; it was essentially a more modern version. However, it was priced at $249 upon launch, significantly lower than the first-gen SE, which cost $279 on release.

The Apple Watch Ultra was an entirely new addition to Apple's smartwatches, debuting also in September 2022. This piece of tech, built with a titanium-made 49mm case, was noticeably larger than the other Apple Watches, equipped with a bigger strap, more buttons, and a 2,000-nits ultra-bright screen. Thankfully, it's lightweight feel did not sacrifice size for comfort. The new bands, the Alpine Loop, Trail Loop, and Ocean Loop, also provided a secure fit.

Although the typical Apple Watch was already designed to enhance fitness, this model was specifically put out for outdoor adventure enthusiasts. It introduced features and enhancements not available on the standard version, including significantly improved battery life. Apple claimed up to 36 hours of continuous use, which could be extended to 60 hours in low-power mode.

There was also a dual speaker system, more microphones, and a better GPS based on dual frequencies to improve accuracy and reduce the chances of getting lost. And if that happened, the Backtrack feature would allow users to retrace their steps and find their way back. All these features, however, came at a cost of $799.

The Apple Watch Series 9 was introduced in September 2023. It retained the design of the previous Series watches, but the screen became brighter and more powerful, with a 2,000-nits display. There were still two size options: the 41mm and the 45mm, offered in aluminum and stainless steel. Also, like the past few Apple Watches, it had a starting price of $399.

Aside from the updates brought by a new OS, there were not many developments on the watch itself. Beyond this, one of the stand-out features was the Double Tap. When a user made a pinch gesture with their fingers, the watch recognized it and performed a primary action, depending on what was displayed on the screen at the moment. Also, there was now an on-device Siri, thanks to its S9 SiP processor, which meant there was no need for it to be connected to the cloud to process questions.

In addition, Apple emphasized a more eco-friendly approach with this watch, announcing that the gadget was now "carbon-neutral." As a result, the bands were reportedly made from recycled material. This, according to the company, was also the reason for not including a charger.

The Apple Watch Ultra 2 retailed at $799, much higher than the Series 9, but at the same cost as the original Ultra watch. It adopted a similar exterior design as its predecessor, coming in one size, 49mm, and a similar pixel resolution. The battery life was also similar, except that the Ultra 2 extended the low-power mode battery life from 60 to 72 hours.

Regardless, the Ultra 2 was a significant upgrade in several ways. One was its newly improved 3,000 nits display, which increased the brightness by 50%. Then there was the introduction of more modern features that were available on the Series 9, such as on-device Siri, and the Double Tap feature. Also, it shipped with the new Apple S9 processor, a step further from the S8 SiP with the 64-bit dual-core processor of the first Ultra. Storage size also doubled on the Ultra 2, going from 32 GB to 64 GB.

Another Ultra 2 feature was sleep apnea detection, which users of the first version didn't get. However, owners of the Ultra 2 also missed out on the blood oxygen sensor of the old Ultra. This was after medical technology brand Masimo accused Apple of stealing its pulse oximetry technology. Apart from these, there was also a notable design change. While the first generation came in 1 color, Ultra 2 had a new jet black titanium option, coupled with a new band, the Titanium Milanese loop.

Nearly a decade after its first smartwatch release, Apple announced the Series 10 on September 9, 2024. It is currently the latest Apple Watch and arguably the best smartwatch on the market. Starting at $399, the Series 10 has a sleek build, is much thinner than its predecessors, and comes in a range of colors and finishes. But, unlike the Series 9, it doesn't come in stainless steel. Instead, owners get the option of an aluminum or titanium case, and there's a new jet-black finish.

Despite a slimmer design, the Series 10 features a bigger screen and more advanced display offered in 42mm and 46mm. There's also a new processor, the S10 SiP, which is faster than previous models. Nothing much has changed for fitness, except that it has better features for swimming. The device can now measure your depth in water with its new gauge. You can also track water temperature and underwater visibility while submerged, and the Tides app and Oceanic + app are great for surfing and snorkeling.