iOS 12.1.3 (build 16D5037a) is an official Apple over-the-air update for the iPhone XS, released on 2019-01-07T18:07:11Z. The update package is 330.97 MB. This is a delta (partial) update that requires 12.1.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: cc347ea9a51c032f042a5ad0dd2e45447dca6498.zip.