iOS 8.2 (build 12D508) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2015-03-09T18:49:05Z. The update package is 482.67 MB. This is a delta (partial) update that requires 8.0.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: a88c82083c7c1c3208cb3599573a0f2a4948a64b.zip.