Until last year there was not an API that allowed apps to download music to the local storage of the watch and play it back in the background. https://develope

Until last year there was not an API that allowed apps to download music to the local storage of the watch and play it back in the background. https://developer.apple.com/videos/play/wwdc2018/504/ https://developer.apple.com/videos/play/wwdc2018/504/