watchOS 5 Compatibility →
From Apple’s watchOS 5 preview:
watchOS 5 requires iPhone 5s or later with iOS 12 or later, and one of the following Apple Watch models:
- Apple Watch Series 1
- Apple Watch Series 2
- Apple Watch Series 3
watchOS 5 is not compatible with the first-generation Apple Watch.
I hope the Series 4 will be a worthy upgrade over my Space Black steel Series 0.