Xiaomi Watch S4 Sport

The Design section of the Xiaomi Watch S4 Sport centers on a 1.43″ OLED/AMOLED touchscreen with a resolution of 466 x 466 px and a pixel density of 326 ppi, protected by sapphire glass rather than a branded damage-resistant alternative. The display supports Always-On mode, and the case measures 46.9 x 46.9 mm with a thickness of 12.6 mm, weighing 49 g in total. A 5 ATM water resistance rating covers the watch to a depth of 40 m, making it suitable for water-based activities. The 22 mm band is replaceable, giving users flexibility in how they wear the watch day to day.

The Xiaomi Watch S4 Sport includes a broad sensor array, covering a heart rate monitor, a pulse oximeter for blood oxygenation tracking, a body temperature sensor, and built-in GPS for location data. Motion and orientation are handled by an accelerometer, gyroscope, and compass, while a barometer rounds out the hardware with atmospheric pressure readings. A cadence sensor and perspiration monitor are not part of the package.

The Xiaomi Watch S4 Sport covers a wide range of activity tracking capabilities, logging steps, distance, pace, and elevation during workouts, while a route tracker records the path taken. It detects activities automatically and supports exercise tagging, making it straightforward to keep a structured record of sessions. On the water side, the watch includes a swim stroke counter and is designed for diving as well. Sleep is monitored continuously, with detailed sleep reports generated over time, and calorie intake tracking adds a nutritional dimension to the overall health picture.

The Xiaomi Watch S4 Sport supports standalone cellular connectivity through a single eSIM, and pairs with both iOS and Android devices over Bluetooth 5.2. NFC is included for contactless interactions, and Galileo satellite support broadens location accuracy alongside the onboard GPS. Wi-Fi and ANT+ are not supported on this model.

The Xiaomi Watch S4 Sport is powered by a rechargeable 586 mAh battery rated for up to 15 days of use on a single charge, and it supports wireless charging for cable-free top-ups. The battery is not removable, and there is no solar charging option on this model.

The Xiaomi Watch S4 Sport packs a solid set of health and smart features, tracking HRV, VO2 max, and resting heart rate, with fast/slow heart rate notifications and a readiness and recovery indicator to give a broader picture of daily wellbeing. It does not include ECG technology, irregular heart rate warnings, or fall detection, and the smart alarm is also absent. On the communication side, the watch can answer calls, handle call control, and deliver wrist notifications and vibrating alerts, backed by a single microphone and voice command support. A silent alarm and stopwatch are on board, and practical extras include phone finder, a camera remote shutter, and fast GPS lock. Internal storage sits at 32 GB, there is no front camera, and the watch carries a one-year warranty.

The companion app is free to download, ad-free, and requires an account to use. It delivers activity reports, an exercise diary, and goal setting alongside calorie burn tracking, water intake logging, weight tracking, and temperature tracking. Inactivity alerts and achievements keep users engaged with their progress, and the app personalises to individual preferences with widget support and calendar sync. Music playback is available directly through the app, and maps are included, though route support and email export are not. On the wellness side, the app covers period notifications, ovulation prediction, and cycle start date prediction, but does not include a barcode scanner or coaching features.

The Xiaomi Watch S4 Sport includes a battery level indicator and passcode protection for basic security and at-a-glance power monitoring. It does not offer an external memory slot, a 3.5 mm headset jack, or compatibility with Windows or Mac OS X.