Cercube Max is not available on the official because it violates Google's terms of service. Instead, it must be installed using alternative methods:
While popular, Cercube Max has faced criticism for occasionally inserting its own banner ads into the app. As a result, many users in communities like r/sideloaded have shifted toward newer alternatives: Cercube Max
Another lightweight alternative favored for its clean interface and lack of independent ads. How to get Cercube for iOS/iPhone/iPad Cercube Max is not available on the official
Enables users to watch videos in a floating window while using other apps. Cercube Max