iOS 11.4.1 (build 15G77) is an official Apple over-the-air update for the iPhone 6s, released on 2018-07-09T17:10:13Z. The update package is 686.65 MB. This is a delta (partial) update that requires 11.2.5 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f5d335f5b01480bebc8a6b9ad3da9f884f2a8f1b.zip.