watchOS 5.0 (build 16R5357a) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm, LTE), released on 2018-08-20T17:09:05Z. The update package is 649.52 MB. This is a delta (partial) update that requires 4.3.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 3663418e91bd123c2f6426633dd44ad5de569742.zip.