iOS 9.3 (build 13E233) is an official Apple over-the-air update for the iPhone 6, released on 2016-03-21T18:56:29Z. The update package is 1.16 GB. 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: d35d3f04386879bc2399610b8c348d27e9558b3a.zip.