iOS 9.3.1 (build 13E238) is an official Apple over-the-air update for the iPhone 5 (GSM), released on 2016-03-31T16:54:36Z. The update package is 997.68 MB. This is a delta (partial) update that requires 8.1.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: bdee1eb32c4106a53cb7a261ea4a3c52e4d472f9.zip.