iOS 9.1 (build 13B143) is an official Apple over-the-air update for the iPhone 5s (Global), released on 2015-10-21T17:16:04Z. The update package is 1013.9 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: 2637a25fe59898f5aca852539bae1abb2e0626e1.zip.