iOS 11.2.1 (build 15C153) is an official Apple over-the-air update for the iPhone 7 (Global), released on 2017-12-13T18:14:36Z. The update package is 391.69 MB. This is a delta (partial) update that requires 11.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ed1b10906b00cb5453b281b3d45f660a10ba462a.zip.