watchOS 4.1 (build 15R5846) is an official Apple over-the-air update for the Apple Watch (42mm), released on 2017-10-20T17:03:56Z. The update package is 223.06 MB. This is a delta (partial) update that requires 4.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 630099dd4280628333aec4a0dcf57b0867b3b3f7.zip.