watchOS 5.3.7 (build 16U674) is an official Apple over-the-air update for the Apple Watch Series 4 (40mm), released on 2020-05-18T17:31:58Z. The update package is 49.37 MB. This is a delta (partial) update that requires 5.3.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 77cffd62ce8f375209dc5d6d2ab3d598a7bb1c79.zip.