Apple
Apple Music live streaming Beats 1 radio station will also begin airing.
To use Apple Music, iPhone and iPad users will need to download and install a new iOS update, iOS 8.4, which will become available on Tuesday morning.
It's clear that Apple Music and iOS 8.4 are releasing Tuesday morning, but it's unclear at the time writing at exactly what time either will be released.
However, Ian Rogers of Beats Music recently tweeted that the iOS update will be available at 8 a.m. Pacific/11 a.m. Eastern. He wrote that Beats 1 will go live an hour later.