The Apple Watch Series 11 offers powerful tools for comprehensive health tracking and seamless integration with your iPhone. Key features include an ECG app to check for signs of atrial fibrillation, continuous heart rate monitoring with irregular rhythm alerts, and advanced sleep analysis with the Sleep Score feature. It also tracks blood oxygen levels and includes a Vitals app that monitors heart rate and breathing data overnight. The watch is 5G enabled and uses Apple Intelligence for smart features like message translation.