iPadOS 8.4 (build 12H4086d) is an official Apple over-the-air update for the iPad Air (China), released on 2015-04-27T17:47:04Z. The update package is 143.03 MB. This is a delta (partial) update that requires 8.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ff45f1487d53d9613736e75461bc324d5f96705c.zip.