Apple Watch Ultra 3 vs Xiaomi Watch S4
Which one should you buy?
Who leads where?
- Health Sensors and FeaturesApple Watch Ultra 3
- DisplayApple Watch Ultra 3
- KasaXiaomi Watch S4
- Positioning and GNSSApple Watch Ultra 3
- Battery and ChargingXiaomi Watch S4
- Water and Dust ResistanceApple Watch Ultra 3
Wins are counted from the official values in the table below; the BUY / CONSIDER / WAIT call comes from each product's own decision box. We do not predict prices.
 AppleApple Watch Ultra 3No reviews yet |  XiaomiXiaomi Watch S4No reviews yet | |
|---|---|---|
| Key Differences | ||
| Case Size | 49 mm | 47.3 mm |
| Processor | Apple S10 | — |
| Battery Life | up to 42 hours | up to 360 hours |
| ECG App | Yes | — |
| Water Resistance | 100m | 5 ATM |
| Health Sensors and Features | ||
| Heart Rate Sensor | Yes | Yes |
| SpO2 Sensor | Yes | Yes |
| ECG Sensor | Yes | — |
| Skin Temperature Sensor | Yes | — |
| ECG App | Yes | — |
| Atrial Fibrillation Notification | Yes | — |
| Sleep Tracking | Yes | — |
| Fall Detection | Yes | — |
| Crash Detection | Yes | — |
| Display | ||
| Size | — | 1.43" |
| Panel | OLED (LTPO3) | AMOLED |
| Resolution | 422x514 | 466x466 |
| Peak Brightness | 3000 nit | 1500 nit |
| Always-On Display | Yes | — |
| Kasa | ||
| Case Size | 49 mm | 47.3 mm |
| Case Thickness | 12 mm | 12 mm |
| Weight | 61.6 g | 44.5 g |
| Case Material | Titanium | Aluminium alloy |
| Positioning and GNSS | ||
| GNSS Receiver | Yes | Yes |
| Dual-Band GNSS | Yes | — |
| GNSS Systems | GPS, GLONASS, Galileo, QZSS, BeiDou | GPS, GLONASS, Galileo, BeiDou, QZSS |
| Battery and Charging | ||
| The figure the maker states | up to 42 hours | up to 360 hours |
| What that figure measures | Normal use | In typical use |
| Capacity | — | 486 mAh |
| Charging Type | Fast charging | Magnetic charging |
| Water and Dust Resistance | ||
| Water Resistance | 100m | 5 ATM |
| IP Rating | IP6X | — |
| Rated Depth | 40 m | — |
| MIL-STD-810 | MIL-STD-810H | — |
| Performance | ||
| Processor | Apple S10 | — |
| Storage | 64 GB | — |
| Connectivity | ||
| Cellular | Optional | — |
| Wi-Fi | Wi-Fi 4 | — |
| Bluetooth | 5.3 | 5.3 |
| NFC | — | Yes |
| Speaker | Yes | Yes |
| Microphone | Yes | Yes |
| Software | ||
| Operating System | watchOS | Xiaomi HyperOS 2 |
| Phone Compatibility | iPhone 11 or later (iOS 26+) | Android and iOS |
Apple Watch Ultra 3 leads on 12 of 15 compared specs.
This table is based on manufacturers official specifications. Winning on paper does not always mean a difference in everyday use.