XIAOMI WATCH S4

Description

Design & Build

• Case: The Xiaomi Watch S4 uses a circular case measuring 47.3 × 47.3 × 12.0 mm.
• Weight: The watch body weighs approximately 44 g without the strap; final wrist weight depends on the selected strap.
• Construction: The design uses a replaceable decorative bezel system, allowing the watch’s external appearance to be changed without replacing the watch body.
• Glass: The front uses scratch- and drop-resistant protective glass. Xiaomi does not specify a separate Mohs hardness rating in the supplied specifications.
• Water Resistance: The supplied specifications do not state an IP rating or a specific water-resistance depth, so the Watch S4 should not be assigned an unverified immersion rating.
• Controls: Physical controls are provided on the right side of the case, including a rotating crown for scrolling and interface navigation.
• Strap: The watch uses a replaceable wrist strap; strap dimensions and material vary by retail configuration.

Display

• Panel: The watch has a 1.43-inch round AMOLED display.
• Resolution: The panel resolution is 466 × 466 pixels.
• Pixel Density: The display provides approximately 326 pixels per inch.
• Brightness: High-brightness mode reaches 1,500 nits, while peak brightness is rated at 2,200 nits.
• Refresh Rate: The display operates at up to 60 Hz.
• Color: AMOLED technology provides individually lit pixels, high contrast, deep black levels, and an always-on display capability.
• Protection: The display is covered by scratch- and drop-resistant glass; Xiaomi does not identify a specific glass manufacturer in the supplied facts.
• Interface: The circular panel is designed for watch faces, widgets, notifications, health data, workout controls, and call management.

Performance

• Platform: The Watch S4 operates on Xiaomi HyperOS 2.
• Processor: Xiaomi does not publish a conventional smartphone-style CPU model, clock speed, or core configuration for the Watch S4 in the supplied specifications.
• Memory: The supplied specifications do not provide a verified RAM capacity or user-accessible storage capacity; unconfirmed marketplace listings should not be treated as official memory specifications.
• Use Cases: The hardware is designed for watch-face rendering, touch and crown navigation, notifications, Bluetooth calling, health measurements, workout recording, and GNSS tracking rather than smartphone-class application performance.
• Operating System: HyperOS 2 provides the system interface, device settings, watch faces, fitness functions, health dashboards, notifications, and connected-watch controls.

Cameras

• Camera Hardware: The Xiaomi Watch S4 has no built-in front camera or rear camera.
• Photography: No megapixel rating, lens aperture, optical image stabilization, autofocus system, video resolution, or camera flash is applicable to this watch.
• Remote Control: Camera-related functions, where available through compatible software, rely on the connected smartphone’s camera rather than an imaging sensor in the watch.

Battery & Charging

• Capacity: The watch uses a 486 mAh lithium-polymer battery.
• Endurance: Xiaomi rates battery life at up to 15 days under typical usage conditions. Continuous GPS recording, always-on display use, frequent Bluetooth calls, frequent health measurements, notifications, and high screen brightness can reduce runtime.
• Charging: Charging is performed through the supplied magnetic charging system.
• Charging Wattage: Xiaomi does not publish a fixed wired charging wattage for the Watch S4 in the supplied specifications; a numeric wattage should therefore not be inferred from smartphone charging standards.
• Charging Compatibility: The watch requires its compatible magnetic charging accessory and is not specified as supporting Qi wireless charging or reverse wireless charging from a smartphone.
• Battery Type: The cell chemistry is lithium-polymer, with a rated capacity of 486 mAh.

Software & AI

• System: Xiaomi HyperOS 2 is the installed smartwatch operating system.
• Health Software: The software supports heart-rate monitoring, blood-oxygen saturation tracking, sleep analysis, stress monitoring, activity records, and workout data.
• Fitness Software: Workout modes use the watch’s motion sensors and positioning hardware to record exercise metrics, route information, duration, and related performance data.
• Watch Faces: The system supports configurable watch faces and display layouts, including options designed for the circular AMOLED panel.
• Notifications: When paired with a compatible smartphone, the watch can display supported notifications and provide wrist-based interaction with selected phone functions.
• AI Functions: The supplied specifications do not identify a dedicated AI processor, an on-device generative-AI system, or a quantified AI feature set; no such specification is assigned here.
• Compatibility: The Watch S4 supports smartphones running Android 8.0 or later or iOS 14.0 or later.

Connectivity

• Bluetooth: Wireless connectivity uses Bluetooth 5.3.
• Bluetooth Calling: The watch supports voice calls through a connected smartphone over Bluetooth.
• Calling Requirement: Bluetooth calling requires the watch to remain connected to the smartphone’s Bluetooth connection.
• Third-Party Calls: Voice calls from third-party applications are not currently supported according to the supplied product information.
• Positioning: The watch includes built-in satellite positioning for outdoor workout and route tracking; the supplied facts do not state a verified GNSS chipset model or a precise band-combination specification.
• Near-Field Connectivity: NFC availability and supported payment functions can vary by market and retail version; no universal NFC payment specification is assigned without a regional model number.
• Phone Support: Compatible phones must run Android 8.0 or later or iOS 14.0 or later.

Colors

• Case Options: The Xiaomi Watch S4 is offered in black and silver case finishes, subject to regional availability.
• Strap Options: Strap color, material, and included accessories vary by market and product package.
• Bezel Customization: The replaceable bezel system allows the watch’s external styling to be changed independently of the display and main case.