If you use Apple Music, you can upload mp3s (preferably ALAC to avoid lossy transcoding because it always converts to AAC) to their servers and stream them from

If you use Apple Music, you can upload mp3s (preferably ALAC to avoid lossy transcoding because it always converts to AAC) to their servers and stream them from any of your devices. For me it's the killer app for Apple Music. It's the reason I switched to it from Spotify.