watchOS 5.0 (build 16R5334f) is an official Apple over-the-air update for the Apple Watch Series 1 (38mm), released on 2018-07-30T17:09:53Z. The update package is 663.51 MB. This is a delta (partial) update that requires 4.2.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 8a50ca5cdaff4bbbc7e89150cd01ae864a00a905.zip.