iOS 9.9.11.4.1 (build 15G5072a) is an official Apple over-the-air update for the iPhone 6s, released on 2018-06-18T17:05:39Z. 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: 911d09369cc90ca72b738c907e56330a577fc8fc.zip.