iPadOS 9.2.1 (build 13D15) is an official Apple over-the-air update for the iPad mini 4 (Cellular), released on 2016-01-19T17:59:36Z. The update package is 1.38 GB. 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: f7a28f5691f61168cd3b17c5a801450cc5d44dc7.zip.