With a choice of more than 50 watch face themes - more than 40 of them with a matching always-on display - the Amazfit GTS 2e smartwatch fits most outfits and occasions. Alternatively, you can personalize the watch face with your own images and use the customizable module to focus on what's important. Huami's BioTracker 2 optical biological data logging sensor can perform 24-hour heart rate monitoring. It covers heart rate zones and alerts when resting heart rate is abnormally elevated. In addition, the sensor has a SpO2 measurement function. If you are doing sustained mental or physical activity, you can read the current SpO2 level here, even if you feel unwell, to get a better understanding of your physical condition. The GTS 2e offers in-depth sleep monitoring that can accurately distinguish between the light and REM sleep periods, monitor sleep breathing status, provide quality analysis and suggestions for improvement based on one night's sleep, and detect daytime naps over 20 minutes. When one activates one of the sports modes, the watch generates a corresponding analysis report after the workout is completed to improve the workout plan. The intelligent detection of sport modes eliminates the need to manually select the sport mode. Thanks to the water resistance up to 50 meters, you can even wear it while swimming.