iOS 9.0 (build 13A4305g) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2015-07-21T19:26:09Z. The update package is 307.87 MB. This is a delta (partial) update that requires 9.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: bac64e6c4dd470d5df147d5e92e7c221a7ba977b.zip.