Calls/texts (with SIM/Bluetooth), fitness tracking (steps, heart rate, SpO2, sleep), and media control, but also feature advanced capabilities like GPS tracking (especially for kids' safety), NFC for access, 4G/Wi-Fi connectivity, built-in cameras, extended battery life, and sophisticated health monitoring (blood pressure/oxygen), running on Android/iOS, becoming standalone mini-phones with seamless app integration and personalized wellness.