iOS 9.3.5 (build 13G36) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2016-08-25T16:53:31Z. The update package is 330.81 MB. This is a delta (partial) update that requires 9.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 9141b19adf1801236afb4bc65fff0df675afdad3.zip.