watchOS 5.2.1 (build 16U5110a) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm), released on 2019-04-29T17:39:02Z. The update package is 482.79 MB. This is a delta (partial) update that requires 5.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 1d74deff51a03e828a03500c9a50e6ea34c8ee9a.zip.