watchOS 5.3.10 (build 16U711) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm), released on 2026-03-24T18:36:25Z. The update package is 484.95 MB. This is a delta (partial) update that requires 5.1.1 already installed. This update is currently signed by Apple, so it can be applied from Settings › General › Software Update.

Payload file: c440cb6fa705c111054ecc50d593a5926b74f65f.zip.