iPadOS 9.2.1 (build 13D15) is an official Apple over-the-air update for the iPad Air (Cellular), released on 2016-01-19T17:59:23Z. The update package is 31.08 MB. This is a delta (partial) update that requires 9.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ac37315ca1792fad6564f2d9f339d21f8589d6fb.zip.