watchOS 3.1 (build 14S452) is an official Apple over-the-air update for the Apple Watch (42mm), released on 2016-09-21T17:00:42Z. The update package is 559.61 MB. This is a delta (partial) update that requires 2.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: b3e48babbda2bbb592fa7d5e2323cdf50a70e698.zip.