iPadOS 9.1 (build 13B143) is an official Apple over-the-air update for the iPad 2 (WiFi), released on 2015-10-21T17:15:47Z. The update package is 811.56 MB. This is a delta (partial) update that requires 8.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: e88f1743456e33a750edee41ff263638c954e327.zip.