2021 New HW21 Smart Watch Men Women IP68 Waterproof Bluetooth Sleep Monitor Fitness Heart Rate Tracker Smartwatch

【MORE FEATURES】The fitness tracker supports more accurate heart rate monitoring, ,blood oxygen, music control, sleep monitoring, message, sedentary remind, incoming call,alarm,dimming,check the phone and more. You can read messages on the fitness tracker from Facebook, What Sapp , Twitter, Line,  etc.

【WIDE COMPATIBILITY】The app supports most smart phones with Bluetooth 5.2,Support system: iOS 10.0 or above,Android 5.0 or above

Parameter

Main Display :  TFT 240*240 ,1.28inch

Bluetooth:Bluetooth 5.2

Type of battery: li-ion battery

Battery:200 mAH

Standby time: about 5-10 days

Compatilbe:IOS 10.0 or above/ Android 5.0 or higher

Introduction to watch function:

Sleep:The watch can record and display the total length of your sleep last night and the length of your deep sleep and light sleep.More detailed analysis and data logging can be viewed in the client

Weather information:The weather page shows the current weather, air quality information, and tomorrow’s status. Weather information needs to be connected to the client before data can be obtained. If the connection is disconnected for a long time, the weather information will not be updated.

Work out:Long press on the exercise page to start an exercise measurement record, there are 8 sports modes to choose from The last workout record information can be displayed on the exercise page.

Message push:The watch can receive notification pushes on the display phonePush item switch can be set inthe client The watch message page can store the last 3 message records

Camera control:When connected to a mobile phone,the watch can be used as a mobile phone camera remote control After turning on the camera on the phone,click on the watch camera control page to trigger the phone camera shutter

Music control:After connecting the phone, the watch can control the phone’ s music player When the phone is playing music, you can use the watch to control the phone to play/pause, previous and next operations.

Smart alarm clock:The smart alarm clock of the watch can be set in the client.Up to 3 alarm clocks can be set When setting the time, the watch will display the alarm icon and vibrate

For the problem that the bracelet can measure the heart rate in things and in the air, the following explanation is made:

1.At present, the mainstream heart rate bracelets on the market adopt the same measurement method. The principle is not complicated, that is, the PMG signal of the radial artery is obtained by the reflective photoelectric measurement method, and the fast Fourier transform is performed on the PPG signal to analyze the frequency domain. To achieve the detection of the human heart rate. To put it simply, it is to use a light to the artery and then reflect it back. Based on the change of the reflected light, the heart rate of the human body is calculated.

2.Due to many factors such as the physiological structure of the human body, the color of muscles and blood, green light is the color with the highest passing rate in the human body. Therefore, the light source of the heart rate sensor uses green light to achieve minimum loss and interference.

3.Heart rate wristband detection focuses on human tissue. Some data is also read for non-human objects. This is a known and normal phenomenon. After the data is based on the principle of light reflection, the heart rate detection will have a reading. This situation cannot be All avoided, so there will be problems with heart rate data in the case of heart rate bracelet (table) in the case of “air test”