iOS 8.1.2 (build 12B440) is an official Apple over-the-air update for the iPhone 4s, released on 2014-12-09T17:49:04Z. The update package is 79.15 MB. This is a delta (partial) update that requires 8.0.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 898ed5a8407187f43d19629838888c13a350c88a.zip.