iOS 11.4 (build 15F5071a) is an official Apple over-the-air update for the iPhone X (GSM), released on 2018-05-07T17:11:37Z. The update package is 243.63 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: a610f3f7a7f10a8f294d4aece728b62a272e933f.zip.