iPadOS 9.3.1 (build 13E238) is an official Apple over-the-air update for the iPad 4 (GSM), released on 2016-03-31T16:52:21Z. The update package is 1.01 GB. This is a delta (partial) update that requires 8.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: b578cfabc55fdbfb13aada62406dcfed94e1dded.zip.