iPadOS 9.1 (build 13B143) is an official Apple over-the-air update for the iPad 2 (GSM), released on 2015-10-21T17:15:48Z. The update package is 811.15 MB. This is a delta (partial) update that requires 8.0.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: c5809b743a6ea07f933d6fe5caa4750d9995c98e.zip.