tvOS 11.4.1 (build 15M73) is an official Apple over-the-air update for the Apple TV 4 (2015), released on 2018-07-09T17:13:37Z. The update package is 536.07 MB. This is a delta (partial) update that requires 11.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 815278f3a5784a4bc892ff602e704421e53c9b1e.zip.