Batteries are consumables. As long as you use them, their service life will decrease day by day.
Apple Watch Series4 uses a larger screen with two sizes, which are 35% and 32% larger than before. At the same time, the dial has been redesigned, and you can customize the dial, such as adding photos. At the same time, a larger screen can display more information, such as boarding information, and a dynamic screen saver can be set. The processor of Apple Watch Series4 is further upgraded; The speaker volume is increased by 15% than before, and the microphone is moved from the back end to the side end, which makes the call experience better. Apple Watch Series4 also adds more security and health features. For example, SOS ambulance function; In the aspect of heart rate monitoring, it can provide low heart rate reminder and even display ECG.