watchOS 5.3.10 (build 16U711) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm, LTE), released on 2026-03-24T18:36:55Z. The update package is 522.86 MB. This is a delta (partial) update that requires 5.0 already installed. This update is currently signed by Apple, so it can be applied from Settings › General › Software Update.

Payload file: 515832edac2889bd4f65150b48624724e6eb2d8f.zip.