April 24, 2015 marked the beginning of a new era in wearables when the original Apple Watch went on sale. In the decade since, Apple has sold over 200 million smartwatches, transforming the device from a fashion-forward companion to a powerful health tool.
The Beginning: The Original Apple Watch
In 2015, it wasn’t the “Series 1”—it was just the Apple Watch. It came in two sizes, had a capacitive touchscreen, a digital crown, interchangeable bands, and an optical heart rate sensor. But even then, there were issues. One of the early controversies was “TattooGate,” where darker tattoo ink interfered with the heart rate sensor’s light-based measurements, causing inaccurate readings or even locking users out of their devices.
September 2016: Series 1 and Series 2
Apple introduced two new versions: the Series 1 with an updated processor and the Series 2 with built-in GPS, swim-proofing, and a brighter 1000-nit display. This was also the year Apple partnered with Nike for the first time, launching the Apple Watch Nike+, which included run-focused watch faces.
By the end of 2016, Apple had sold 11.9 million watches, surpassing Rolex to become the world’s top-selling watch brand by revenue.
Series 3: Cellular Freedom
Launched in 2017, Series 3 introduced cellular connectivity, allowing users to take calls, send texts, and stream music without their phones. It also included a barometric altimeter and the first heart rate alerts for unexpected spikes when inactive.
Series 4: Design Refresh and ECG
In 2018, Apple rolled out a new design with edge-to-edge displays, increased case sizes (40mm and 44mm), and introduced fall detection and ECG capabilities for detecting abnormal heart rhythms. These features set the tone for Apple's future health ambitions.
Series 5: Always-On, Compass, and More
The 2019 model brought an always-on display and a built-in compass. Apple also added a noise detection app and cycle tracking for menstrual health. For the first time, titanium models were offered, expanding into the luxury watch segment.
Series 6 and SE: Blood Oxygen and Accuracy Boost
In 2020, the Series 6 added blood oxygen monitoring (later disabled in the U.S. due to a patent dispute). It also marked a major improvement in GPS accuracy. Apple launched the more affordable SE model, offering many core features at a lower price.
Series 7: Bigger and Smarter for Triathletes
Released in 2021, Series 7 featured a larger screen, thinner bezels, and better durability. WatchOS 9 introduced a triathlon mode with touchless transitions—automatically detecting when users switch from swim to bike to run.
Series 8, Ultra, and SE 2: Rugged and Refined
In 2022, Apple launched three models: Series 8 with crash detection, a second-gen SE, and the all-new Apple Watch Ultra. The Ultra brought a rugged 49mm design, dual-frequency GPS, and doubled battery life. It was a favorite among adventurers and athletes.
Series 9 and Ultra 2: Refinement Over Revolution
The 2023 updates focused on performance, with a new chip and a “double tap” gesture for quick interactions. While not groundbreaking, they laid the foundation for more gesture-based controls.
Series 10: Bigger, Smarter, and Focused on Sleep
Launched in 2024, the Series 10 introduced sleep apnea notifications and larger case sizes (42mm and 46mm). The Ultra 2 got a sleek all-black edition with a carbon diamond-like coating.
What Comes Next?
Looking ahead, the Apple Watch Series 11 and Ultra 3 are expected this September. Rumors point to blood pressure trend monitoring, satellite emergency calling, and possibly 5G RedCap for low-power connectivity. Apple may also be laying the groundwork for smarter on-device AI with more neural engine cores.
Some users hope to see features like an action button on the Series 11, more battery life, a slimmer body, and a redesigned heart rate sensor to bring back SPBO2 monitoring.
Final Thoughts
From its humble beginnings to a full-fledged health device, the Apple Watch has consistently evolved year after year. Whether you’re celebrating the 10th anniversary by closing your rings or simply appreciating how far smartwatches have come, one thing is clear: Apple’s not done innovating.
