iOS 10.3.1 (build 14E304) is an official Apple over-the-air update for the iPhone 7 (GSM), released on 2017-04-03T17:00:41Z. The update package is 585.27 MB. This is a delta (partial) update that requires 10.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 76dacf3b58e00bf7ffe30753a8c4ceba75029387.zip.