iOS 11.4 (build 15F79) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2018-05-29T17:15:58Z. The update package is 765.65 MB. This is a delta (partial) update that requires 11.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: d70357088b931e7d93ac2c042584caf72f4248f3.zip.