iOS 11.4 (build 15F5049c) is an official Apple over-the-air update for the iPhone 8 (GSM), released on 2018-04-16T17:08:09Z. The update package is 277.37 MB. This is a delta (partial) update that requires 11.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 4bd218d7b942bd9a73da6a3cbc52568c64aeadc3.zip.