iOS 12.3 (build 16F5129d) is an official Apple over-the-air update for the iPhone X (GSM), released on 2019-04-08T17:05:01Z. The update package is 317.78 MB. This is a delta (partial) update that requires 12.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 96523fd23df07f18f2a08eee8af98415f8395061.zip.