iOS 11.3 (build 15E216) is an official Apple over-the-air update for the iPhone 7 (GSM), released on 2018-03-29T17:13:30Z. The update package is 1.4 GB. This is a delta (partial) update that requires 10.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 3fd61b6007e9250da867b25f299308516e8cc11d.zip.