| key specs |
| Display Size | 36mm | 50mm |
| Compatible OS | Android 8.0 or above, iOS 12.0 or above | - |
| Dial Shape | Round | Square |
| Display Type | AMOLED | Super AMOLED |
| Ideal For | Unisex | - |
| Strap Colour | - | Black, Blue, Teal |
| general |
| Brand | Xiaomi | Fastrack |
| Model | Watch S4 15th Anniversary Edition | Revoltt FS1 Pro |
| Release date | May 23, 2025 | April 24, 2023 |
| Model Name | Xiaomi Watch S4 15th Anniversary Edition | Revoltt FS1 Pro |
| Dial Colour | Black | - |
| Dial Shape | Round | Square |
| Size | Regular | - |
| Touchscreen | 1.43 | - |
| Interchangeable Strap | Yes | - |
| Water Resistant | 5 ATM | IP68 |
| Usage | Regular | - |
| Ideal For | Unisex | - |
| Strap Colour | - | Black, Blue, Teal |
| dimensions |
| Width | 47.3 | - |
| Height | 47.3 | - |
| Thickness | 12 | - |
| Weight (g) | 44.50 | - |
| product details |
| Sensor | Heart Rate Monitor, Stress, Sleep | Heart Rate tracker |
| Compatible Device | Android and iOS | - |
| Battery Type | 486mAh | - |
| Notification | - | Yes |
| Notification Type | - | Smart Notification |
| Rechargeable Battery | - | Yes |
| Other Features | - | Activity Tracker, Heart Rate Tracking, Bluetooth Calling , Voice Assistance, 110+ Sports Mode Tracking, In Built Mic & Speaker,IP68 Rating, Sleep Monitor, Fast charging |
| connectivity features |
| Bluetooth | Yes | Bluetooth |
| Bluetooth Version | 5.3 | - |
| Wi-Fi | Yes | - |
| GPS | Yes | - |
| Other Connectivity Features | NFC, Galileo, Glonass, Beidou, QZSS | - |
| Call Function | - | Yes |
| platform and storage features |
| Operating System | HyperOS 2 | - |
| Compatible Operating System | Android 8.0 or above, iOS 12.0 or above | - |
| camera and display features |
| Display Resolution | 466 x 466 | 410 X 502 |
| Display Size | 36mm | 50mm |
| Display Type | AMOLED | Super AMOLED |
| Other Display Features | - | Always-on Display |
| fitness and watch functions |
| Step Count | Yes | Yes |
| Calorie Count | Yes | - |
| Heart Rate Monitor | Yes | Yes |
| Alarm Clock | Yes | - |
| Date & Time Display | Yes | - |
| Language | English | - |
| Other Fitness Features | - | Activity Tracker, 110 Sports Mode Tracking |
| Other Watch Functions | - | Bluetooth Calling, Voice Assistance, In Built Mic & Speaker, IP68 Rating |