watchOS 4.1 (build 15R5835d) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2017-10-09T17:04:55Z. The update package is 566.5 MB. This is a delta (partial) update that requires 3.2.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 19d2579cbdde8dfa12c2bb805b4b0dc70079b568.zip.