If you use black, the editing process takes longer and there are icons and text that are difficult to change, so that it can contrast with a dark background.
After yesterday there was the theme of ios 12 white, now it's the turn that is black for Samsung device suporte android Nougat And Android Oreo and Marshmallow Very Nice theme.
But in this black version, there is only one type. Because there were some who experienced an error alias the UI system was stopped, so there was no more center clock version on this iOS 12 black theme.
For more information about all this, you can see the video below.
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