iOS 9.9.11.1 (build 15B93) is an official Apple over-the-air update for the iPhone 6s, released on 2017-10-23T17:07:43Z. The update package is 1.82 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: 7ca40fb9bdb50080feb05c22679cd7599663b576.zip.