Still not sure how to position, price or even name the macOS version of Longplay. It can only play non-DRM protected albums, so it's only a subset of what the iOS app can play, and it doesn't have a way so far to manage your music so you're reliant on the Music.app.
Might call it "Longplay Collector's Edition" and just sell it directly through Gumroad or so. Might upgrade it later to a "proper" Longplay for macOS when either Apple adds APIs for third-party apps to play Apple Music content (let me dream!), or when I let you drop your manually curated albums from a folder on your disk and let you manage those through the app.
The iOS version has a sizeable audience, but I feel like it'll be tiny for macOS given these constraints... so probably not worth it to fret too much over this.
Looking forward to getting it out. It's been a great learning experience. It's my first Mac app based on #AppKit and #SwiftUI and I'm proud of the result. (And my low-level audio player in there turned out more robust than the built-in one that handles DRM'ed content on iOS...).