Along with iOS 15.6 and macOS 12.5 Monterey, Apple released watchOS 8.7 with bug fixes, performance improvements, and security updates. Since the Apple Watch Series 3 won’t be compatible with watchOS 9 this fall, this will most likely be the last update it will receive.
watchOS 8.7: Security Updates
The update won’t change the Apple Watch much, but it does include more than two dozen security updates that affect every corner of the operating system, from audio to the neural engine to Wi-Fi. All updates also appear as part of the iOS 15.6 and iPadOS 15.6 updates, including several critical updates that could lead to arbitrary code execution.
How watchOS 8.7 . to get
Go to the Apple Watch app on iPhone to install watchOS 8.7. On the My Watch tab, select General, then Software Update and Download and Install. Your Apple Watch must be charged at least 50 percent, placed on a charger, and within range of your iPhone.