iOS 9.2.1 (build 13D15) is an official Apple over-the-air update for the iPhone 6, released on 2016-01-19T18:20:42Z. The update package is 302.93 MB. This is a delta (partial) update that requires 9.0.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 27428446b19bc8cd78abbaada5ae741529e21a9b.zip.