Does the DMA mandate that they actually implement extra apps/features, or just provide the API surface for others to do so? Like, just to pick the first one on your list - any reason they can't just let it point at an arbitrary app that's tagged as providing music (and, I presume, that implements some standard API to query songs or w/e). Does the law really want Apple to integrate with ex. Spotify, or just make it possible for Spotify to integrate the same way as Apple's own music app?