iOS 11.4 (build 15F5049c) is an official Apple over-the-air update for the iPhone X (GSM), released on 2018-04-16T17:08:13Z. The update package is 292.14 MB. This is a delta (partial) update that requires 11.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f2a6a848565786209a283dd4a4358733102439e5.zip.