Importance Note: Please connect the watch via APP Da Fit not on Bluetooth. The time and date will be synced from phones after connecting. The watch could work most functions without connecting to a phone, such as HR, BP, step, calorie, sleep monitor etc. Heart Rate:The fitness tracker measures your heart rate at your wrist Blood Pressure:Equipped with blood pressure monitor, help you check and save the history date on watch. When measure the BP, please put the hand at the same height as the heart that will be more accurate, but kindly note it couldnt be accurate as medical device. Sleep Monitor:Automatically monitor total effective sleeping time from 9:00 pm to 9:00 am every day, you can better understand your sleeping quality. How it works: Detect your heart rate and excise such as the wrist movement to analyze. Call and message remind:Phones Message vibration reminder and can reject the call, check message on watch. Step: All day track your steps. The working principle: record it according the swing of arm. the 3D sensor is sensitive, whether swing a large or a little amplitude, the sensor will collect all of them. APP:Da Fit, Find it from google play or app store, had better try to download before purchase Additional Function: blood oxygen, calories, distance, remote controler of phones camera and music player, weather forecast etc. General: CPU: NRF52832 Acceleration: 3-axis G-sensor Heart rate: Dynamic heart rate detection Key button: Single point touch System: Support Android 4.4, IOS 9.0 and above systems Material Body: PC Band: PU Display Display size: 1.3 in Display type: IPS Battery Battery: 230mAh Work time: 7 days