iPadOS 8.1.3 (build 12B466) is an official Apple over-the-air update for the iPad Air (Cellular), released on 2015-01-27T17:55:04Z. The update package is 1.11 GB. This is a delta (partial) update that requires 7.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 7648238cceffb88c8e92b6ad4ecf3d6b2c220756.zip.