Apple instantly releases iOS 11.4.1 Beta 3 to registered Developers and public as well with a build number 15G5072a.
iOS 11.4.1 beta 3 contains security with bug fixes and improvements.
Downloading iOS 11.4.1 beta 3
The registered developer can download the iOS 11.4.1 beta 3 from the Apple Developer Program with an appropriate configuration profile or Apple Beta Software Program through OTA (Over the Air) by navigating Settings >> Software Update >> Download and Install.
Along with that Apple also releases third betas of macOS 10.13.6 and tvOS 11.4.1.
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