iOS 8.4.1 (build 12H318) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2015-07-30T18:00:09Z. The update package is 53.69 MB. This is a delta (partial) update that requires 8.4.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: c2e5f53ecd27ce2ce6d1b5b33f8bfaa6e1cd55b5.zip.