iPadOS 9.1 (build 13B5137) is an official Apple over-the-air update for the iPad 4 (GSM), released on 2015-10-12T16:56:59Z. The update package is 1.21 GB. This is a full OTA update that can be applied from any compatible base version. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 02d509281c8db8a5823b7a24bcb45ec8b9a341ac.zip.