iOS 9.9.11.4 (build 15F5049c) is an official Apple over-the-air update for the iPhone 6s, released on 2018-04-16T17:07:16Z. The update package is 1.85 GB. This is a full OTA update that can be applied from any compatible base version. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 330b61f118f69eff18da44f7502148a06adb521b.zip.