Compatibility: Android 5.0 (L OS) or higher, 1.5GB RAM or more - iOS: 9.0 or higher, iPhone 5 and new models. (Smartphone compatibility and function availability may vary according to region, network provider and device.) Operating system: Tizen Based Wearable OS 5.5 Memory (RAM + storage): 1GB + 8GB Connectivity: 2.4 GHz WI-FI 802.11 b/g/n, NFC, GPS/Glonass/Beidou/Galileo Battery: 247 mAh (+43 hours) Processor: Exynos 9110 / 1.15 GHz CA53 64-bit dual-core Durability: 5 ATM + IP68 / MIL-STD-810G Sensors: Optical heart rate sensor (8PD), electrocardiogram (ECG), accelerometer (up to 32 G), gyroscope, barometer, ambient light Health features: sleep, blood pressure, heart rhythm (ECG), atrial fibrillation detector (Afib), fall detector, blood oxygen concentration (Sp02), menstrual cycle Sports features: real-time analysis, automatic recognition and targeted workouts