iOS 12.1 (build 16B5089b) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2018-10-22T17:02:01Z. The update package is 133.22 MB. This is a delta (partial) update that requires 12.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: e3e179764d3555f3eb23a8f781987c411e57db36.zip.