iPadOS 8.1 (build 12B5410) is an official Apple over-the-air update for the iPad 4 (WiFi), released on 2014-10-20T17:59:02Z. The update package is 1.77 GB. This is a delta (partial) update that requires 8.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 7fa5770adee308f7e64c4a0c50af8438d42e55fd.zip.