CategoryFeatureFunctionalityConnectivityBT (Bluetooth) CallAllows you to make and receive phone calls directly from the watch using its built-in mic and speaker, without needing to hold your phone.Transactions/AccessNFC (Near Field Communication)Enables contactless payments (if supported by the watch/bank) and can often be used for keyless entry/door unlocking systems.DisplayHD (High Definition)Ensures a crisp, clear, and vibrant screen for easily reading messages, viewing health data, and interacting with the interface.Health MonitoringHealth SmartWatchProvides comprehensive 24/7 tracking of vital signs, including heart rate, blood oxygen level ($\text{SpO}_2$), sleep quality, and steps/calories.