The Nike Apple Watch S4 has been redesigned and re-engineered with built-in electrical and optical heart sensor, a new Digital Crown with haptic feedback, varying heart rate notifications and tons of new features for fitness fans. On top of these, it's also swim-proof. The S4 has over 30% larger display and 50% louder speaker than the S3. Use Walkie-Talkie, make calls and send messages. Listen to Apple Music, podcasts and use Siri in new ways right from your wrist. The built-in GPS lets you send and receive text messages, answer phone calls and receive notifications when connected to your iPhone via Bluetooth and Wi-Fi. It also works for distance, pace and route mapping in workouts. Track your runs and receive personal reminders and weather updates. ConnectivityGB memory. iOS operating system. Bluetooth 5 connection. Wi-Fi. Display information40mm AMOLED screen. Touchscreen. BatteryTypical usage time of up to 1 day. Low usage time of up to 0.75 day. Physical specificationSize: medium. T10.7mm. Weight 36.7g. FeaturesWater resistant. Dust resistant. Make calls. Answer calls. Read texts and reply to texts. Read emails and reply to emails. Receive social network notifications. View calendar. Displays weather. Music player. Heart rate monitor. Pedometer. Accelerometer. GPS. Accessories included: Case, Band, 1m Magnetic Charging Cable and 5W USB Power adapter.