watchOS 5.3 (build 16U569) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm, LTE), released on 2019-07-22T19:20:31Z. The update package is 154.81 MB. This is a delta (partial) update that requires 5.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: b59ff89a2473a1b53c7911bd708ce237c38241e8.zip.