Apple didn't spill the beans on specific changes in this build other than bug fixes and improvements. iOS 12 Developer beta 7 includes a number of new features, such as improved notifications, memoji for the iPhone X, performance refinements, Screen Time for monitoring usage, and better security.
Apple has however, pulled the Group FaceTime feature according to a report from The Verge. "Group FaceTime has been removed from the initial release of iOS 12," said Apple in a message to developers. Instead, Group FaceTime "will ship in a future software update later this fall." The final version of iOS 12 won't arrive until September or October. A new public beta is expected to arrive later this week.
Apple has taken notice, pulling the OTA update from its servers. Developers still have access to the IPSW file, which is available for download and manual installation via Apple's Developer website.
We’ll stay tuned for a new build of the iOS 12 Developer beta 7 release to become available for over the air.
Update: Apple has also removed the update from the Apple Developer Center.
Source: The Verge