Redesigned Mail app still missing from iPadOS and macOS betas

Apple released the first betas of iOS 18.3 and macOS 15.3 to users, but unfortunately for Mac and iPad users, iPadOS 18.3 and macOS 15.3 still don't have the redesigned Mail app. The new Mail app was introduced with iOS 18.2 and has a more modern look with smart categorization. It is expected that the new Mail app will be available on iPad and Mac with iPadOS 18.4 and macOS 15.4.