iOS 9.1 (build 13B5136) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2015-10-06T17:54:06Z. The update package is 1.33 GB. This is a delta (partial) update that requires null already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 5b0efde6e0e3b88aef2796d8d889f2037fa051b5.zip.