iOS 10.3 (build 14E5277a) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2017-03-16T16:56:31Z. The update package is 409.14 MB. This is a delta (partial) update that requires 10.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 6feb20367d40e84ad32aee01bf8b97ec9cdf407b.zip.