Table of Contents
Sport & health: precision, diving, robustness
GPS & track accuracy
On the road, both cut corners cleanly. In urban canyons, the dual frequency reduces “frontage jumps”. In the undergrowth, wandering almost disappears. My traces superimposed on reference GPX remain clean, with a medium bias <3m in town. Sufficient for interval training as well as trail hiking. Clearly.
Useful sensors & metrics
Apple : Fast and stable PPG, reliable ECG, SpO2, skin temperature for nighttime tendencies, accident detection, whistle 86 dB — discreet but reassuring. The new training screens (load, recovery) give clear direction, not a fog of numbers.
Samsung : BioActive combining PPG + ECG + BIA. Body composition serves as a safeguard during the dry or recovery phases. Cardio coaching relies on history, not just today’s output. Good surprise: the variability of the sessions forces the watch to “listen” to the body. You can feel it.
Diving & extreme sports
Ultra 2 : certification EN13319depth 40m recreational, dedicated Depth/Oceanic+ app. Readability at 3000 nits and effective Night Mode. For supervised freediving and recreational diving, it’s perfect.
Galaxy Watch Ultra : 10ATM, IP68, MIL-STD-810Hquick button for profiles (triathlon, route return, expedition). Heat, altitude, dust: she takes it. It’s not a dive computer, but it’s a very credible adventure watch.
Method & evidence of use
Field tests over 5 days (Paris, October 2–6, 2025): 6 running outings (parks + banks of the Seine), 2 cycling sessions, 1 short hike. 1 s recording, GNSS L1+L5 active, comparison with reference GPX traces. Autonomy measured in mixed scenario (notifications, offline music, sleep). Test log recorded session by session. Nothing exotic, just real life.
Price, availability and shopping experience
Apple Watch Ultra 2 is usually found around €899 in France, sometimes a notch lower depending on the bracelet. eSIM operator: check the compatibility of your plan before purchase (pro, multi-SIM, roaming). A poorly chosen line and you lose the interest of LTE at the worst time.
Galaxy Watch Ultra starts at ~€699 public price, often seen between €599 and €649 on offer. Samsung pushes one-off ODRs; read the small text, always. To understand the entire range (sizes, options), consult our guide to choosing the best Samsung Galaxy Watch and avoid buying by reflex.
Want a no-nonsense opinion on this specific model? We did it: expert opinion on Samsung Galaxy Watch Ultra (hard points, real strengths, no marketing script).
Verdict & recap
iPhone, recreational diving, mountain safety : Apple Watch Ultra 2. Ultra-consistent software environment, diving certification, integrated siren. Simple. Effective.
Android, endurance, body tracking : Galaxy Watch Ultra. Multi-day battery life, BIA for redialing, durable housing. Less expensive, more durable. Frankly, it tips the scales.
Equality on the screen (up to 3000 nits), serious robustness on both sides, dual frequency GNSS for a clean trace. The phone often decides. And he must decide.
Express recap
- Phone : iPhone → Ultra 2; Android → Watch Ultra.
- Autonomy : Samsung advantage (2–3 real days, more in economy).
- Diving : Apple advantage (EN13319, 40 m, dedicated apps).
- Sensors : ECG/SpO2/Temperature of both; Samsung adds BIA.
- Robustness : MIL-STD-810H on both sides; IP68/10 ATM at Samsung, WR100/IP6X at Apple.
- Price : Ultra 2 ~€899; Watch Ultra €599–699 depending on offers.
Author : David Deteve, editor & GPS watch tester — real uses, sourced measurements, no empty promises.
