iOS 8.3 (build 12F5061) is an official Apple over-the-air update for the iPhone 6, released on 2015-03-24T16:54:16Z. The update package is 140.86 MB. This is a delta (partial) update that requires 8.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 9feff78e0bd48c73edfba4814f6a8efc652c1d97.zip.