iOS 9.9.11.4 (build 15F5049c) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2018-04-16T17:07:14Z. The update package is 1.8 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: cf896ead3a06dc6d9639ee56433371a045e56881.zip.