iOS 8.1 (build 12B411) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2014-10-20T17:59:09Z. The update package is 1.18 GB. This is a delta (partial) update that requires 7.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 428ecd356e84bfd25869c777d116e2fbd4ef0481.zip.