iOS 12.1.3 (build 16D39) is an official Apple over-the-air update for the iPhone X (Global), released on 2019-01-22T18:08:51Z. The update package is 286.03 MB. This is a delta (partial) update that requires 12.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 1bb2877410763f192513ae4cb2d3fda4f7087770.zip.