iOS 9.3 (build 13E237) is an official Apple over-the-air update for the iPhone 4s, released on 2016-03-28T16:52:16Z. The update package is 932.72 MB. This is a delta (partial) update that requires 8.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 7e9a2873f2474d21f16afa829c5425d3252c1fdd.zip.