iOS 9.1 (build 13B143) is an official Apple over-the-air update for the iPhone 6s, released on 2015-10-21T17:16:05Z. The update package is 252.18 MB. This is a delta (partial) update that requires 9.0.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 29133f8052f6dc59cec4ae1d6fdcdf0a0460b4d7.zip.