Note: The bike odometer has been updated and can switch between miles and kilometers. You can select your preferred miles/kilometers display format in the app settings. (Before using the G bike computer for the first time, you need to download the app and share your training data by linking your Trainingpeaks account.) Sync Function: The professional bike speedometer app supports uploading your riding data via Bluetooth. The G wireless bike computer can also sync cadence and heart rate data to the app via Bluetooth, and then integrate with Trainingpeaks for easier data sharing and more comprehensive training analysis. ANT+ Sensor Compatibility: This GPS bike computer is compatible with heart rate monitors, speed and cadence sensors, and allows connection to power meters via ANT+. If the sensor is connected to the speedometer, you will get all the data needed for multiple rides (additional sensors required). 4. Satellite Positioning System: Compatible with global navigation systems GPS, BeiDou, Galileo, and GLONASS. Fast positioning speed and high accuracy. Calculates sunrise and sunset times based on GPS information, achieving automatic GPS time calibration and accurate time information (Note: Positioning speed is affected by weather changes and other factors). Automatic backlight and waterproof: This wireless bike speedometer features a large, anti-glare screen with automatic backlighting, ensuring clear visibility even in sunlight. It displays various data, allowing for easy and clear reading day or night. An IPX7 waterproof rating ensures this GPS bike speedometer functions properly in the rain.