watchOS 5.3.7 (build 16U674) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm, LTE), released on 2020-05-18T17:32:06Z. The update package is 56.95 MB. This is a delta (partial) update that requires 5.3.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 097fe27a9bcaf9f0b8466402db016fe53f4611cf.zip.