From Fall Detection to Hypertension — 10 Apple Watch innovations that changed the game

The first Apple Watch debuted almost 11 years ago on April 24, 2015, and while Cupertino didn’t invent the smartwatch, Apple’s square-shaped wearable is easily the most popular and recognizable smartwatch in the world today.

2026 marks 50 years of Apple, and to celebrate the brand’s history, I’ve taken a look back through the brand’s entire catalog of smartwatches — from the original ‘Series 0’ to the current Series 11, Ultra 3, and SE 3 — to narrow down the ten most significant Apple Watch innovations that revolutionized wearable tech.

2015: First Apple Watch debuts

The year is 2015. ‘Uptown Funk’ is booming on the car stereo, ‘Pizza Rat’ is trending on Instagram (TikTok has yet to launch in the U.S), selfie sticks have invaded public space en masse, and Apple has a shiny new wearable computer called the Apple Watch.

The original Apple Watch lacked the health, fitness, and safety features found in the best Apple Watch models in 2026. It also lacked waterproofing, cellular connectivity, and onboard GPS, relying on a paired phone for location data. The device was groundbreaking and hugely popular, nonetheless.

A status symbol for techies, Apple moved over eight million smartwatches in the first year it went on sale. Like today’s flagship, the original model came in two sizes, with a starting price of $349 for the 38mm model and $399 for the 42mm option. Key features included support for Apple Pay, an onboard heart rate monitor, and Apple’s nifty digital crown.

The first Apple Watch also debuted alongside the official Apple Watch App Store, which offered roughly 3,000 apps at launch.

2016: Onboard GPS

The following year, Apple announced the Apple Watch Series 1 and Apple Watch Series 2, beginning an annual September release schedule that the brand still sticks to today. These upgraded models had the same basic design as the original, but now with splash-resistance, and perhaps more notably, onboard GPS.

This meant that users could now track an outdoor workout on their watch without having to carry along a phone for location data, a huge perk for runners, walkers, hikers, and cyclists.

2017: Apple Watch goes cellular

Apple wasn’t the first brand to offer a cellular-capable smartwatch — that was Samsung — but 2017’s Apple Watch Series 3 certainly popularized the concept of on-wrist connectivity, sans-smartphone. For the first time, Apple Watch wearers could receive calls and messages on their watch with no phone in sight.

The LTE-capable Apple Watch Series 3 model used eSIM to connect to mobile internet, with the watch’s display serving as the cellular antenna.

2018: Fall Detection

One of Apple’s most well-known safety features, Fall Detection, officially made its debut in 2018 alongside the Apple Watch Series 4. Now a mainstay on all Apple Watch models, Fall Detection uses the device’s onboard gyroscope and accelerometer to determine when a user takes a tumble and how hard they fell.

In 2022, Apple expanded on this useful bit of safety tech by adding car Crash Detection via the Apple Watch Series 8. Like Fall Detection, it can automatically call for help in an emergency and share location data with loved ones and rescuers if you’re unresponsive.

2018: FDA-approved ECG readings

2018's Apple Watch Series 4 was also the first smartwatch on the market with FDA-approved electrocardiogram (ECG) functionality capable of detecting Atrial fibrillation (AFib).

This was the exact moment, in my mind, that the Apple Watch began to shift away from being a companion device to the iPhone, focused on connectivity features, and more of a standalone device centered around a user’s health, fitness, and safety.

ECG reading took just 30 seconds and required you to simply press your thumb and finger against the digital crown and back of the device. Two years later, Samsung would add a similar FDA-approved ECG functionality via the Galaxy Watch 3.

2019: Always-on display

The Apple Watch Series 5 in 2019 ushered in the era of always-on displays. The watch’s innovative LTPO panel allowed the screen to remain active at all times, using a low refresh rate to save battery.

This meant that your Apple Watch could now display the time and your choice of complications without the need to raise your wrist, tap the screen, or press a button to wake it. It’s worth noting that Apple was far from the first smartwatch maker to introduce an always-on display, but the brand no doubt popularized the feature.

2020: Blood oxygen monitoring

2020’s Apple Watch Series 6 saw the introduction of another marquee health feature: blood oxygen saturation (SpO2) monitoring. While the Series 6 was one of the world’s first mainstream smartwatches with the feature, its debut would ultimately land Apple in hot legal water with rival, Masimo, which claimed to own the patents behind the tech.

The Apple vs Masimo debacle would ultimately result in a U.S. import ban on later Apple Watch models (the Series 9 and Ultra 2) and years of back-and-forth litigation.

Nevertheless, the feature launched just in time for the COVID-19 pandemic. By monitoring the percentage of oxygen in a user’s bloodstream (anything 95% and up is considered ‘normal'), the feature could potentially indicate early signs of a viral infection based on consistently low readings. Of course, it was no substitute for an actual COVID-19 test.

2022: Apple Watch Ultra debuts

2020 also gave us the debut of the more wallet-friendly Apple Watch SE, with a starting price of $279. However, it would be another two years before Apple’s tough-built Apple Watch Ultra arrived.

Arguably the most groundbreaking model since the debut of the very first Apple Watch Series 0, the $799 Ultra promised far better battery, a tougher build quality with a sapphire crystal display and titanium alloy case, an additional, programmable ‘Action Button,’ and double the water resistance of the standard and SE models. It also offered a massive, ultra-bright screen packed into a larger-than-life 49mm case.

Designed with outdoor enthusiasts and endurance athletes in mind, the Apple Watch Ultra found a curious fanbase amongst tech and finance bros eager to swap out their Rolex Submariner for something even cooler.

2024: Sleep apnea detection

Apple was a little late to the sleep apnea detection train, but 2024 was when Cupertino officially started taking sleep tracking seriously. While prior models monitored your sleep patterns and total time spent resting, this was the first time the Apple Watch could inform you whether signs of the deadly condition, which often goes unnoticed, are present in your sleep data.

For sleep apnea detection to work, users need to wear their Apple Watch Series 9 or newer for at least ten nights in 30 days.

2025: Hypertension alerts

As of writing, hypertension alerts remain unique to only Apple Watches. Offered on the Series 9 and newer, along with the Ultra 2 and 3, the device needs 30 days of wrist data to predict whether or not the user shows potential signs of high blood pressure.

To do this, the watch uses the onboard heart rate sensor to monitor how your blood vessels respond to your heartbeat. That data gets fed through an algorithm to determine whether or not the user is at risk of hypertension.

(Honorable mention) 2025: Satellite SOS messaging

Currently only available on the Apple Watch Ultra 3, the new emergency SOS messaging feature is designed to let users connect to rescuers and/or loved ones from off-the-grid via satellite with the ability to share location data and a text-based message.

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