watchOS 5.3.10 (build 16U711) is an official Apple over-the-air update for the Apple Watch Series 3 (42mm, LTE), released on 2026-03-24T18:35:14Z. The update package is 102.23 MB. This is a delta (partial) update that requires 5.3.9 already installed. This update is currently signed by Apple, so it can be applied from Settings › General › Software Update.

Payload file: 8b6e938eb825dcd1b6f9b1636ffb62da5bec4bd8.zip.