In a tweet shared this afternoon, Troughton-Smith said that based on evidence he's discovered, Apple appears to be working on new UIKit-based Music, Podcasts, and Books apps for macOS, all three of which will join the TV app that Apple has said is in the works.
Separate apps for each of these services suggest that Apple is planning to break up the iTunes app for Mac, which is where Podcasts, Movies, and TVs are available at the current time. Apple already has a Books app, but an updated version or separate app that includes audiobooks could be in development.
I am now fairly confident based on evidence I don't want to make public at this point that Apple is planning new (likely UIKit) Music, Podcasts, perhaps even Books, apps for macOS, to join the new TV app. I expect the next wave of Marzipan apps. Grain of salt, etc
̵1; Steve Troughton-Smith (@stroughtonsmith) April 5, 2019
Apple in macOS Mojave introduced the groundwork for cross-platform iOS and Mac apps, and Apple introduced dedicated Mac apps for Stocks, Home, Apple News, and Voice Memos. All of these apps were based on iOS apps, and with new the software coming in 2019, additional iOS apps could be brought to Mac to replace iTunes.
And yes, this means much-discussed and long-awaited break up of iTunes. Finally!
– Steve Troughton-Smith (@stroughtonsmith) April 5, 2019
Troughton-Smith has, in the past, shared accurate info on Apple's plans based on hints and code discovered in current versions of Apple's operating systems.
Apple will macOS 10.15 alongside iOS 13 at its 2019 Worldwide Developers Conference set to kick off on June 3.