iPadOS 9.1 (build 13B5119e) is an official Apple over-the-air update for the iPad 4 (WiFi), released on 2015-09-23T17:55:04Z. The update package is 1.21 GB. This is a delta (partial) update that requires null already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 9d15ed17ecc184aa9df0386c0c86c83ac3457971.zip.