iOS 9.3 (build 13E5225a) is an official Apple over-the-air update for the iPhone 4s, released on 2016-03-01T18:13:39Z. The update package is 96.9 MB. This is a delta (partial) update that requires 9.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 395a49ab031645411df06a118f33ac6299eaa08d.zip.