iOS 7.1.2 (build 11D257) is an official Apple over-the-air update for the iPhone 4 (GSM / 2012), released on 2014-06-30T18:00:03Z. The update package is 158.75 MB. This is a delta (partial) update that requires 7.0 already installed. This update is currently signed by Apple, so it can be applied from Settings › General › Software Update.

Payload file: 3c203b3c83988f791da9e49e7315417e2d4136c3.zip.