Specifications Waterproof Rating : IP67 Thickness: 3mm Materials: Titanium alloy Weight: Approximately 0.102 oz Colors: Silver, Space black Chipset: Goodix GR5515GGBD Memory(ROM+RAM) :1 Mb + 256 KB G-Sensor: ST LIS2DW12 Bluetooth Version: 5.1 MobileAPP-GPS: Yes Heart Rate Sensor: Goodix GH3026 Battery Type: Lithium-ion polymer battery Battery Capacity: Approximately 17.5 mah Charging time: 1 hour Theoretical Standby Time: 10-15 days Normal Usage Time: 4-6 days Charging: Magnetic Software Function&App Compatibility : Supports Android 5.0 and above; iOS version 10.0 or above Compatibility Software: Compatible with Nova Ring App software functions Activity: Distance/Calories/Steps Statistics/7-day vigorous activity etc Multi-sports modes: 19 kinds of conventional sports +5 kinds of GPS sports(Running, Cycling, Rope Jumping, Fitness, Mountaineering, Yoga, Golf) Heart rate: app launches heart rate test/whole-day dynamic heart rate trend and data analysis/heart rate data analysis/recent 7 heart rate measurement trends/heart rate historical data Sleep: Sleep data statistics, sleep proportion, sleep score, sleep analysis, average sleep heart rate, etc Blood oxygen: APP launched blood oxygen test/blood oxygen data of the last 7 times/blood oxygen saturation measurement trend of the last 7 times/blood oxygen history data HRV: APP launched HRV test/recent 7 HRV data/average HRV/stress history data during sleep Stress: APP launched stress test/pressure measurement trend of the last 7 times/pressure history data Others: Unit format, sedentary reminder, low battery reminder, heart rate warning Wechat&Apple: Support APP multi-language support:2 Languages: English, Japanese Support OTA: Yes APP: Nova Ring