watchOS 5.3.7 (build 16U674) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm), released on 2020-05-18T17:31:53Z. The update package is 59.5 MB. This is a delta (partial) update that requires 5.3.5 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: d01268330588369bba451523f1caebd7047fa3a8.zip.