iOS 9.9.12.1 (build 16B6092) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2018-10-30T17:04:04Z. The update package is 2.1 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: d00c5ee59c7a8a06e061eb03d925e05fa9407d5d.zip.