iOS 11.4 (build 15F79) is an official Apple over-the-air update for the iPhone 6s, released on 2018-05-29T17:16:27Z. The update package is 1.34 GB. This is a delta (partial) update that requires 10.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 9f17d4bac55dfde9cda77a3b9016d7d1d09a0cb1.zip.