watchOS 5.0 (build 16R5363a) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm, LTE), released on 2018-08-31T17:15:23Z. The update package is 653.7 MB. This is a delta (partial) update that requires 4.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: a1bee14cb6ae97220e3a69f9a7a4527ed83e9c09.zip.