iOS 15.7.3 (build 19H307) is an official Apple over-the-air update for the iPhone 7 (GSM), released on 2023-01-23T18:49:35Z. The update package is 2.4 GB. This is a delta (partial) update that requires 14.4.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 9fe351e40c5ae55b57d3b9cfd6f102bacfd1b765.zip.