Apple Watch Series 4 Review: Still Worth It in 2025?

The Apple Watch Series 4 launched in September 2018 as the first Apple Watch with an FDA-approved ECG sensor and a display 30% larger than its predecessor. By January 2, 2025, Apple formally classified it as vintage—and that raises a sharp question for anyone scrolling secondhand listings in 2025: is $110 of refurbished Apple hardware still worth it, or a liability dressed up as nostalgia?

Release Year: 2018 · Sizes Available: 40mm, 44mm · Processor: S4 SiP with 64-bit dual-core · Status: Vintage · Display: LTPO OLED Retina

Is the Apple Watch Series 4 outdated?

Yes—technically and officially. Apple classified the Series 4 as vintage on January 2, 2025, meaning it has been out of distribution for more than five years (Apple defines vintage products as those out of distribution for more than five years; Series 4 eligible for repairs if parts available per PhoneArena). All aluminum and stainless steel 40mm and 44mm models fall under this designation worldwide.

The practical gap between the Series 4 and current hardware is significant. The S4 chip is two generations behind the S6, which itself is now three years old. The Series 4 lacks an always-on display, blood oxygen sensing, and any of the smarts introduced in watchOS 11. App loading, Siri responsiveness, and fitness tracking loops all feel slower on older hardware, according to hands-on comparisons (UpTrade).

Age and release timeline

Apple announced and launched the Series 4 on September 12, 2018, with a redesigned chassis that offered a 30% larger display area compared to the Series 3. It was the first Apple Watch to include an FDA-approved ECG app, a milestone that positioned it as genuinely medical hardware at consumer pricing.

Apple shipped watchOS 5 at launch, then continued supporting the Series 4 through nine years of updates until watchOS 11 arrived in 2024 and dropped compatibility entirely. That nine-year support window is longer than most competitors manage, but the hardware ceiling became inescapable by 2025.

Comparison to newer models

The gap between the Series 4 and the Series 6 is the most relevant comparison for budget buyers. The Series 6 adds a 20% faster S6 processor, an always-on display, blood oxygen sensing, and full compatibility with current and future watchOS releases. At $140 certified refurbished versus $110 for the Series 4, most reviewers recommend spending the extra $30 (UpTrade).

The Series 4’s display at 1000 nits brightness is still visible in direct sunlight, and its LTPO OLED Retina panel holds up well for basic notifications and fitness tracking. But for anything requiring real-time health data or app responsiveness, the age of the S4 chip shows.

How old is an Apple Watch Series 4?

The Apple Watch Series 4 is six years and four months old as of early 2025, having launched in September 2018. Apple’s product lifecycle treats anything out of distribution for more than five years as vintage, and the Series 4 crossed that threshold on January 2, 2025 when Apple updated its vintage products list globally.

This means the Series 4 has been without new retail availability since approximately 2020—likely earlier given how quickly Apple’s product cycles move. For a device running a 64-bit dual-core S4 chip designed in 2018, this age brings real constraints on what it can do in 2025.

Release date details

The Series 4 launched alongside the iPhone XS on September 12, 2018, at Apple’s “Gather round” event. The redesign was the most significant since the original: the display grew to 40mm and 44mm options (from 38mm and 42mm), the Digital Crown gained haptic feedback, and the speaker was 50% louder than the Series 3.

The 44mm model displays 368 by 448 pixels across 977 square millimeters of screen area. The 40mm model shows 324 by 394 pixels across 759 square millimeters (Apple Support documentation). Both sizes use LTPO OLED Retina panels capable of 1000 nits peak brightness.

Support timeline

Apple supported the Series 4 with major watchOS updates for nine years—an unusually long window. The final update was watchOS 10, which the Series 4 received alongside the Series 5, SE, and Series 3. When watchOS 11 launched in 2024, the Series 4 was dropped from the compatible devices list.

End-of-support means no security patches, no new features, and potential incompatibility with newer iPhone models as Apple may require current watchOS versions for full functionality. Vintage status also means Apple Authorized Service Providers may have limited repair parts available, though repairs are still possible while stock lasts.

Is the Apple Watch Series 4 still supported?

No. watchOS 11 dropped support for the Apple Watch Series 4, and it now runs only watchOS 10—the last update it will ever receive. This is a hard cutoff, not a gradual phase-out. Apple’s support pages confirm the Series 4 is incompatible with watchOS 11 and all future operating system updates.

The lack of software updates means the Series 4 will never gain the features introduced in watchOS 11, 12, or whatever comes next. More critically, it also means no security patches. As the iPhone ecosystem evolves and new Bluetooth and notification protocols emerge, the Series 4 may gradually lose compatibility with apps and services designed for current watchOS versions.

Software updates status

watchOS 10 was the Series 4’s final operating system. Released in September 2023, watchOS 10 brought a redesigned interface with widget-like Smart Stacks and new watch faces. The Series 4 runs this software smoothly, but anything beyond that is locked out.

Apple’s historical support pattern suggests the Series 4 will remain compatible with basic iPhone pairing for several more years, but the pace of deprecation will likely accelerate as Apple encourages users toward newer hardware. The current iPhone 16 requires watchOS 11 for full health integration features, which already puts the Series 4 at a disadvantage.

End-of-life info

Apple’s product lifecycle has three stages: active (full support and distribution), vintage (limited service availability), and obsolete (no repairs or parts). The Series 4 entered vintage on January 2, 2025. It will become obsolete after approximately seven years from last distribution—likely around 2027—after which no Apple Authorized Repair Provider will be able to service it.

Until that date, repairs remain possible if parts are available, but vintage status often means longer wait times and potentially higher repair costs as supply of genuine Apple components dwindles. Users holding onto Series 4 units in 2025 should anticipate eventual obsolescence and plan accordingly.

Is the Apple Watch Series 4 worth it?

For budget fitness tracking in 2025, the Apple Watch Series 4 is worth it only in a very narrow set of circumstances: if you can find one for under $80, don’t need always-on display or blood oxygen sensing, and are comfortable with a device that will never receive another update. At $110 certified refurbished, the value proposition is marginal—but it exists.

Certified refurbished Apple Watch Series 4 units start at $110 in 2025 (UpTrade). For $30 more, the Series 6 at $140 offers a substantially better experience with current software support, faster processing, and features that remain relevant. The Series 4’s ECG and fall detection still work, and for basic notifications, timekeeping, and exercise logging, it remains functional.

Pros and cons in 2025

Trade-in value

Trade-in values for the Series 4 are negligible in 2025. Apple trade-in and most third-party services offer very little for a watch in this vintage tier. Selling directly on eBay or Facebook Marketplace yields more—UK eBay listings show used Series 4 units around £30—but buyers are increasingly aware of the support limitations.

Regional pricing varies significantly. In South Africa, used GPS models range from R4,000-8,000, with Cellular versions around R8,000 (YouTube reports from regional sellers). In the US, certified refurbished remains the safest bet for a device that’s been properly tested and reset.

What are common problems with the Series 4?

The Apple Watch Series 4’s most common problems in 2025 stem from its age rather than defects. Battery degradation is universal after six-plus years of charge cycles—expect significantly shorter battery life on used units unless the battery has been replaced. Apple’s battery service for vintage products may be limited, and third-party battery replacements risk damaging the water resistance rating. For those interested in the Apple Watch Series 4, you can find more details about the iPad Air 2 giá 2025.

The S4 chip, while solid for its era, shows its age in app loading times and Siri responsiveness. Fitness tracking loops take longer to sync, and third-party apps designed for current watchOS versions may run poorly or not at all. The lack of software updates also means the Series 4 cannot leverage health features introduced in watchOS 11.

Hardware issues

The most frequently reported hardware issue is screen delamination on older units that have been exposed to moisture or impact. The Series 4 is water resistant to 50 meters, but repeated swim exposure in chlorinated or salt water degrades the seals over time. The Digital Crown haptic mechanism can also collect debris, making it feel gritty or less responsive.

The ceramic and sapphire crystal back houses the health sensors including the electrical heart rate sensor for ECG functionality. These typically remain functional on well-maintained units, but cracked backs from impacts do occur and are expensive to repair on vintage hardware.

Battery and performance

Battery life on the Series 4 was rated at up to 18 hours at launch, but after years of use, a used unit may struggle to last a full day without charging. Third-party battery replacement services exist, but sourcing genuine Apple batteries for vintage models is increasingly difficult.

Performance in 2025 is adequate for basic functions—notifications, time, and standard fitness tracking work acceptably—but app loading is noticeably slower than newer models, and watchOS 10’s more demanding interfaces can feel sluggish on the S4 chip. Series 4 still handles notifications, time, fitness, and sleep tracking adequately in 2025 with battery replacement (YouTube reviewer assessments), but the user experience degrades with each new app version optimized for faster processors.

Apple Watch Series 4 Specifications

Six specs worth noting: the display sizes, processor generation, storage capacity, connectivity options, and health sensor suite. These define what the Series 4 can and cannot do relative to current hardware.

The implication: even though these specs were flagship-grade in 2018, the absence of blood oxygen sensing and always-on display—a standard feature since Series 5—makes the Series 4 feel dated compared to current budget alternatives.

Timeline

The Series 4’s trajectory from flagship to vintage spans six and a half years—a remarkably long active life for consumer electronics.

Confirmed vs. Unconfirmed

Most facts about the Series 4 in 2025 are confirmed from tier-1 and tier-2 sources. A few areas remain genuinely uncertain.

Final Verdict: If you’re looking for a budget-friendly Apple Watch in 2025, we highly recommend skipping the Series 4 and opting for the Apple Watch Series 6.

— UpTrade (Tech Blog)

The Series 4 Apple Watch still does everything that I want from a smartwatch in 2025.

— YouTube Reviewer (Content Creator)

The Apple Watch Series 4 was a landmark device that brought medical-grade ECG to a mass-market wearable. In 2025, it remains functional for basic fitness tracking and notifications, but its vintage status and lack of software updates make it a hard sell even at $110. The Series 6 at $140 offers a materially better experience with current watchOS support, faster processing, and an always-on display that the Series 4 can never provide.

Related reading: USB-C to HDMI adapters

Shoppers debating the Series 4 at $110 refurbished might find the Series 6 worth buying guide equally relevant for the 2020 Series 6 under $120.

Frequently asked questions