iOS 9.3.1 (build 13E6238) is an official Apple over-the-air update for the iPhone 6, released on 2016-03-31T16:50:36Z. The update package is 1.38 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: e9ee19496f06f1264c7509b4d38978e6419ea9a0.zip.