iOS 9.1 (build 13B5136) is an official Apple over-the-air update for the iPhone 6s, released on 2015-10-06T17:54:06Z. The update package is 1.43 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: 1486a7ee8ccdd1fcc47d8a3e61f17e982e2a9b94.zip.