The update also enables irregular heart rhythm notifications on Apple Watch Series 1 - 4 models, it can detect signs of AFib, the most common form of irregular rhythm, and the 2nd most common cause in the world. watchOS also adds several other Apple app Infograph watchfaces like the Mail, Message, Phone, etc. Apple also added a Walkie-Talkie toggle from Control Center

Starting today, the ECG app on Apple Watch Series 4 marks the first direct-to-consumer product that enables customers to take an electrocardiogram right from their wrist, capturing heart rhythm in a moment when they experience symptoms like a rapid or skipped heart beat and helping to provide critical data to physicians. The irregular rhythm notification feature on Apple Watch can now also occasionally check heart rhythms in the background and send a notification if an irregular heart rhythm that appears to be atrial fibrillation (AFib) is identified.

This update includes new features, improvements and bug fixes:



- New ECG app on Apple Watch Series 4 (US and US territories only)

* Allows you to take an electrocardiogram similar to a single-lead electrocardiogram

* Can indicate whether your heart rhythm shows signs of atrial fibrillation—a serious form of irregular heart rhythm—or sinus rhythm, which means your heart is beating in a normal pattern

* Saves ECG waveform, classification and any noted symptoms in a PDF on the Health app on iPhone to share with your doctor



- Adds the ability to receive an alert if an irregular heart rhythm that appears to be atrial fibrillation is detected (US and US territories only)



- Enables direct access to supported movie tickets, coupons, and rewards cards in Wallet when tapped to a contactless reader



- Receive notifications and animated celebrations when you achieve daily maximum points in a day during an Activity competition



- New Infograph complications for Mail, Maps, Messages, Find My Friends, Home, News, Phone, Remote



- Manage your availability for Walkie-Talkie from Control Center

To take an ECG, it requires the Series 4's electrodes in the back crystal and the Digital Crown, place your finger on the Crown and wait for 30 seconds. Although Apple Watch can generate the equivalent of a single-lead medical ECG, Apple cautioned that this is not intend to replace traditional methods of diagnosis and should not be used to monitor or track diseases without doctor's description.