watchOS 3.0 (build 14S5278d) is an official Apple over-the-air update for the Apple Watch (42mm), released on 2016-07-05T16:46:54Z. The update package is 463.28 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: 13260041012ad25c08a647cc64abc32c9f12ed48.zip.