Introducing the HAYLOU RS4 Plus smartwatch! It is equipped with a 1.78-inch Retina AMOLED display and a professional sports tracker made of metal and health management functions. Key features include 105 sport modes, 100+ online watch faces, SpO₂ heart rate and sleep and pressure monitoring. It is said that it is also equipped with novel features such as women's health tracking, to-do list, wave..