TraviaTechPie Review

TL;DR — 24 hours, 30 hours, 12 days. Those are the three headline battery figures, and putting them in one table is close to meaningless: Apple publishes the exact test script, Samsung’s number is quoted with the always-on display running, and Garmin’s manual does not say whether the display was on, off, or anything else. Two other things the spec sheet hides: the Venu 4 is a 2025 product competing with two 2026 ones while costing the most, and the Galaxy Watch 9’s headline health features need not just an Android phone but a Samsung phone. The spec that decides this purchase is which phone is already in your pocket.

The Story

I set out to build a clean three-way table and could not. Not because the numbers are hard to find — because the numbers are not commensurable, and nobody says so.

Every roundup you will read puts 24 hours, 30 hours and 12 days in adjacent cells as though they answer the same question. They do not. One of those figures comes with a published, auditable test protocol. One comes with a single sentence of hand-waving. One is measured in a display mode the others were not. The gap between 24 hours and 12 days is real, but it is nothing like 12 times.

So this comparison is organised differently. Where a number is solid, I will say where it came from. Where it is not, I will say that too — because for a purchase this size, knowing which figures you can lean on matters more than having a full table.

The Age Gap Nobody Puts in the Table

Start here, because it reframes everything else.

• Apple Watch Series 12 — announced September 9, 2026.
• Galaxy Watch 9 — announced July 22, 2026, on sale August 7.
• Garmin Venu 4 — announced September 17, 2025.

The Venu 4 is a full product generation older than the other two. It is also, at $549.99, the most expensive of the three by a margin — $150 more than the Series 12’s $399 starting price, $170 more than the 40mm Bluetooth Galaxy Watch 9 at $379.99. And it has no cellular option at any price.

That is not automatically a mark against it. Garmin’s release cadence is slower because Garmin’s hardware changes less, and as you will see below, not changing the hardware turns out to have a concrete regulatory payoff. But if you are comparing on price, you are comparing a year-old device against two current ones, and every roundup I checked left that out.

The Spec Sheet, With Its Sources Shown

A note on the middle column before you read it. Apple publishes a full specification page that reads like a document. Samsung’s US site carries some figures — thickness, price, the update commitment — but its dedicated specification URL does not resolve and the rest of the sheet is locked inside JavaScript-rendered product pages. Garmin’s product pages are also JavaScript-rendered and its support site refuses automated requests outright, though its owner’s manual is plain HTML and, as you will see, the single most useful document of the three. So the evidence quality is genuinely uneven, and I have marked it rather than smoothing it over.

° = figure could not be confirmed on the manufacturer’s own site and comes from secondary sources. Unmarked rows were read off the manufacturer directly. Treat the marked Samsung and Garmin rows as softer than anything in the Apple column — not wrong, just unverifiable at the source, which is a different kind of number to buy on.

What Samsung does publish where anyone can read it is instructive: the price, the thickness, and the five-year update commitment — $459.99 for the 44mm LTE sits on its own buy page. The display resolution, the RAM, the battery footnote do not. That tells you which parts of a spec sheet a company considers load-bearing, and it is not the parts an engineer would pick.

The Battery Numbers Measure Three Different Things

Here is the part that actually matters, and it takes a minute.

Apple: 24 hours normal, 38 hours Low Power, 10 hours outdoor workout. Apple publishes the script. This is the specification page’s wording, verbatim:

> “All-day battery life testing includes: 300 time checks, 90 notifications, 15 minutes of app use, a 60-minute workout with music playback from Apple Watch via Bluetooth, and 6 hours of sleep tracking over the course of 24 hours.”

You can argue with whether that resembles your day. You cannot argue about what was measured. And a detail worth catching: the 38-hour Low Power figure is not the same test run longer — it is a separate test with more interactions packed into it.

Garmin: 12 days smartwatch mode (45mm), 10 days (41mm). Garmin’s owner’s manual publishes seven distinct modes, which is more granularity than either rival offers:

The two music rows are not a duplication — they are different modes that happen to carry identical figures, which is its own small tell about how finely these numbers are actually resolved.

And here is Garmin’s statement of conditions, in full:

> “The actual battery life depends on the features enabled on your watch, such as wrist-based heart rate, phone notifications, GPS, internal sensors, and connected sensors.”

That is the whole thing. No interaction count, no display setting, no pulse-ox sampling rate. Garmin has not published a battery methodology anywhere a buyer can read it, and the manual is the most detailed document it offers.

The display setting is the gap that matters most, and I want to be careful about it. Garmin’s specification page does not state whether the always-on display was enabled for the twelve-day figure. Reviewers who have tested the watch with always-on enabled report getting a fraction of the headline number — the figures circulating land around a third of it — but that is measured by third parties, not published by Garmin, and Garmin has not confirmed the test condition either way. Which is exactly the problem: the most consequential variable in the number is the one nobody will put in writing.

Samsung: up to 30 hours, quoted with the always-on display enabled °. That is the opposite convention to how Garmin’s figure is usually read — but note the marker. I could not retrieve Samsung’s measurement footnote from Samsung, so even the condition attached to the condition is secondhand.

So the honest summary is this. Garmin genuinely lasts far longer than the other two — that is not in doubt and it is the main reason to buy one. But “12 days versus 24 hours” is not the comparison. If the third-party always-on figures are right, the realistic gap for someone who wants a watch face they can glance at is closer to a few days against one: still a decisive win, and a very different number from the one on the box. The finding is that you cannot check this. Two of the three vendors do not publish enough to let you normalise their own figures.

The Deciding Spec Is Your Phone

None of the above will determine your purchase. This will.

• Apple Watch Series 12 requires an iPhone. iPhone 11 or later on iOS 27. There is no Android support and there never has been. One restriction, clearly stated.
• Garmin Venu 4 works with either. “A compatible iPhone or Android smartphone.” It is the only genuinely cross-platform option here.
• Galaxy Watch 9 requires Android — and its health features require a Samsung. This is a two-tier restriction and it is the one people get wrong.

Unpack that last one, because it is the single most consequential fact in this comparison. There are two separate requirements here and they are easy to run together. The first is the watch itself: the Galaxy Watch 9 runs Wear OS and pairs with a phone on Android 13 or newer, from any manufacturer. The second is Samsung Health Monitor — the app that delivers ECG, irregular heart rhythm notifications and blood pressure, which are the features Samsung markets hardest. That app states its own, different requirement: “a Galaxy smartphone with Android 12 or later.” That number is Samsung’s, and it is also a trap — the Watch 9 will not pair below Android 13 in the first place, so the effective floor for ECG and blood pressure is Android 13 on a Galaxy phone, not Android 12 on anything.

So the watch works on a Pixel and the headline health features do not. Be precise about the size of that loss, because it is routinely overstated in both directions. What you actually lose is the Samsung Health Monitor set — ECG, irregular rhythm notifications, blood pressure. Samsung Wallet, notifications and the general Samsung Health tracking continue to work in some form on non-Samsung Android, with feature availability varying by region and by what the phone supports. The clean, verifiable statement is the narrow one: buy this watch for its cardiac features on a non-Samsung phone and those specific features will not run.

So the cheapest watch here carries the most lock-in, and the most expensive carries the least. You are paying roughly a $150 premium for the Venu 4 and part of what you are buying is the freedom to change phones without rebuying a watch.

Worth saying plainly: Apple’s restriction is stricter in absolute terms — no Android at all — but it is also completely unambiguous. Nobody buys an Apple Watch expecting it to work with a Pixel. People absolutely do buy a Galaxy Watch expecting it to work fully with one.

The New Apple Watch Is Behind the Old One

The regulatory picture is the strangest thing in this comparison, and it runs the opposite way to intuition.

From Apple’s own support document, verbatim:

> “Hypertension Notifications might not be available on Apple Watch Series 12 or Apple Watch Ultra 4 in your region, as additional regulatory clearances for the feature for these models are in process.”

Apple redesigned the heart sensor, and a redesigned heart sensor resets the regulatory clock in every market that cleared the old one. So in a substantial number of countries the brand-new watch does less, health-wise, than the one it replaces. I went through the full shape of this in the Series 12 comparison — and the Ultra line inherited the same problem. Apple names no countries; the tallies circulating come from press counts.

Now hold that next to Garmin. Garmin’s ECG app has accumulated clearances across a long list of markets — the US, the UK, the EU, Australia and Switzerland among many others — on hardware that has not been redesigned. Its stability is a direct consequence of the slower hardware cadence that makes the Venu 4 look dated on paper. Garmin still says “the ECG app is not available in all regions,” so check your own, but it is not waiting on a clock it restarted itself.

And Samsung’s blood pressure feature, which reached the US market well after its debut elsewhere, is worth reading carefully: Samsung positions it as a wellness feature, not an FDA-cleared medical one, and it requires calibration against a real cuff. A cuff you already own, using a watch to interpolate between calibrations. That is a legitimate design and it is not the same thing as a cleared blood-pressure device.

If cleared cardiac features are the reason you are buying, that ordering — Garmin stable, Apple in flux, Samsung’s flagship BP explicitly not cleared — is close to the inverse of the brand hierarchy most people assume.

Nobody Paywalls Your Heart Rate

Briefly, because it is a common worry and the answer is reassuring.

• Garmin Connect+ is $6.99/month or $69.99/year, and Garmin’s own release states: “All existing features and data in Garmin Connect will remain free.” The paid tier is AI insights and dashboards.
• Apple Fitness+ is $9.99/month or $79.99/year and is entirely optional. No Series 12 health feature sits behind it.
• Samsung Health has no mandatory subscription.

So none of the three charges you for a core health metric. But notice that Samsung’s gate is not a fee — it is the hardware lock described above. Free, and available only if you keep buying Samsung phones. That is a cost, just not one with a price tag.

Who Should Actually Buy Which

• You own an iPhone and want the best all-round watch. Series 12, and it is not close — the competition is iPhone-incompatible or, in Garmin’s case, a deliberately narrower product. Check whether hypertension notifications are cleared in your country first; if they are not and that feature matters, a discounted Series 11 is a rational purchase.
• You own a Galaxy phone. Galaxy Watch 9. You get the full feature set, the brightest display of the three, body composition nobody else offers, and the only published update commitment — five years. It is also the cheapest. On a Samsung phone this is a genuinely strong buy.
• You own a non-Samsung Android phone. Venu 4, or a Pixel Watch, but not a Galaxy Watch 9 — you would pay for sensors whose headline app refuses to run.
• You train seriously, or you resent charging things. Venu 4. Multi-band GNSS, days of battery instead of hours, and the most stable regulatory footing. Accept that you are buying 2025 hardware at the highest price of the three, and that nobody — Garmin included — will tell you what display setting the twelve-day figure assumes.
• You expect to switch platforms in the next few years. Venu 4 is the only one of the three that survives the move.

The Takeaway

The three most-quoted numbers in this comparison — 24 hours, 30 hours, 12 days — are produced by three incompatible methodologies, and only one vendor publishes enough for you to check. That is the practical lesson: a spec sheet is a document written by a marketing department under legal supervision, and comparing across companies means comparing their disclosure policies as much as their hardware.

The decision itself is simpler than the table makes it look. Your phone picks your watch. Everything above is about what you get to notice once that constraint has already chosen for you — and about which company was willing to show you its work.

Source: Apple Watch Series 12 Tech Specs · Garmin Venu 4 Owner’s Manual · Samsung Galaxy Watch 9

Photo: Dawn Patrol Surf Tracking / Unsplash