watchOS 5.3 (build 16U5537b) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2019-05-28T17:12:12Z. The update package is 131.11 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: dbfebc67acf1aee0fb02cb611d1ae922d9274bb1.zip.