watchOS 5.3 (build 16U6569) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm), released on 2019-07-22T19:20:04Z. The update package is 106.97 MB. This is a delta (partial) update that requires 5.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: efeb34e64c537152e2bae9285f383b571e6392c3.zip.