iOS 8.4.1 (build 12H321) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2015-08-13T18:05:14Z. The update package is 335.27 MB. This is a delta (partial) update that requires 8.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: a47b12ac6bd3366a8927547bfec381110b66194c.zip.