Apple has released watchOS 7.3, alongside iOS 14.4. While the iOS release mainly consists of bug fixes and security updates with a few tiny tweaks to existing features (like better QR code reading), watchOS actually brings some notable features, especially if you live in one of the four countries for which ECG is now available.
For Japan, Mayotte, Philippines, and Thailand, the addition of ECG support (and the related irregular heart rhythm warning) is a big deal. For everyone else, you get a new Unity watch face as part of Appleās Black History Month celebrations and the time Time to Walk feature for Fitness+ subscribers.