The Apple Watch Ultra 4 is the best watch Apple has ever built. For some of you it’s still money thrown away, and for others it’s the biggest jump since the first Ultra. Which case applies comes down to one question: which watch are you wearing right now? I’ll go through each model one by one. All figures come from Apple’s data sheet.
What’s Actually New
Battery: 50 hours of normal use instead of 42. In low power mode, 84 hours instead of 72.
Charging: 15 minutes on the cable now gives you up to 18 hours of runtime. On the Ultra 2 and Ultra 3 it was 12. Going from 0 to 80 percent still takes about 45 minutes. Important: fast charging only works with the new charging puck that’s included. The old puck on your nightstand can’t do it.
Sensors: the watch now measures heart rate every five seconds in the background, and heart rate variability up to 24 times more often than before.
Daily readiness: a score from 0 to 10, recalculated every morning from your activity, training load, vitals and sleep, along with a recommendation: recover, take it easy, ready, or full power.
And one sentence decides this whole topic: daily readiness only exists on the Ultra 4 and the new Series 12. Not on the Ultra 3, not on the Ultra 2, and no update will change that, because the feature depends on the new sensors.
What Stays the Same
The 3000 nit, 49 mm display was already on the Ultra 2. The titanium case is the same, as is the size. Diving to 40 meters, the siren and satellite aren’t new either, since satellite arrived with the Ultra 3. If you own an Ultra 3, you’re already holding this watch in terms of look and feel.
You Have an Ultra 3
Then the answer is no. You have the same display, the same case, the same depth gauge, the same siren and satellite. What you gain is 8 more hours of battery, 6 more hours after a 15-minute charge, one chip generation and daily readiness. For roughly $980, on a watch that’s one year old?
Do the math on the 8 hours in real life: with 42 hours you get through two days, and with 50 hours you also get through two days. A third day isn’t happening either way. That leaves daily readiness, which genuinely is new. Even so: keep it.
You Have an Ultra 2
This is where it gets serious for the first time, because of something that has nothing to do with health: your watch has no satellite connection. That arrived with the Ultra 3. If you hike, go on tours, head into the mountains or sail, you currently have nothing when there’s no signal. With the Ultra 4 you can send an emergency call with no cell service and no Wi-Fi, free for two years from activation.
Then there’s the battery: 36 versus 50 hours. That’s the difference that makes a weekend without a charger work. Plus two chip generations, from the S9 to the S11, and daily readiness.
If your Ultra 2 mostly shows notifications and comes along to the gym, satellite isn’t an argument for you. In that case, read the Series 12 section below.
You Have the First Ultra from 2022
No long discussion needed: upgrade. There’s no satellite, the display does 2000 instead of 3000 nits, which you notice outdoors in the sun immediately. Battery goes from 36 to 50 hours, and from the S8 to the S11 is three generations.
On top of that, something no spec table shows: your battery is four years old. Your watch definitely doesn’t hit the 36 hours from the data sheet anymore. Check battery capacity in settings and you’ll know where you really stand.
You Have a Regular Apple Watch
This isn’t an upgrade, it’s a move into a different class of device. And that has to be said honestly in both directions.
What you gain:
✓ 50 instead of 24 hours of battery
✓ Satellite connection
✓ Depth gauge to 40 instead of 6 meters
✓ A titanium case that takes more abuse
✓ Siren
✓ 3000 instead of 2000 nits
What you lose, and most videos leave this out: the Ultra 4 weighs 63 grams. A Series 12 starts at 32 grams in 42 mm and just under 39 grams in 46 mm. So compared with the smaller Series you’re wearing nearly twice the weight on your wrist. You notice it during sport, while sleeping, and on slim wrists visually too. The Ultra only comes in 49 mm, and there is no smaller version.
My advice: if you wear your watch at night to track sleep, try the Ultra on in a store first. Not for two minutes, but properly. People who return an Ultra almost always do it because of size and weight, not the technology.
The Part Most People Miss: The Series 12
The Series 12 has the same S11 chip as the Ultra 4. It has the same daily readiness feature, the same new sensors and the same Vitals app. It starts at about $490, the Ultra 4 at about $980.
Put plainly: if your reason for upgrading is the new health features, and for most people who write to me that’s exactly it, then with the Ultra 4 you’re paying roughly $490 for things that have nothing to do with health. For battery, satellite, diving, titanium and brightness.
✓ Series 12 if you want the new health features, can charge daily and don’t go where cell service drops out.
✓ Ultra 4 if you hike, dive, travel long distances or want to wear the watch for two days without a charger.
✓ SE 3 from about $290 if notifications and step counting are enough for you. It doesn’t have daily readiness, but many people only use those basics anyway.
Verdict
Ultra 3: keep it, the difference is too small for the money. Ultra 2: upgrade if you’re outdoors a lot, otherwise look at the Series 12. First Ultra: upgrade, no question. Regular Series: only if you genuinely need battery, satellite or diving, and try the weight on first. If you only want the new health features, the Series 12 gives them to you for half the price.
The most expensive option isn’t always the right one. With this generation, for the first time, the difference isn’t in health. It’s in the terrain.
For Your New iPhone
People upgrading their watch usually have a new iPhone too. You’ll find my winners in the comparison of the best iPhone 18 Pro cases and in my iPhone 18 Pro screen protector test. If you’re waiting for the foldable iPhone, see my tests of iPhone Duo cases and iPhone Duo screen protectors. And my free Charge Check shows how fast your charger really charges.