Tidal, Deezer


Could someone with experience with music subscription services please advise. My confusion is that these music services advertise that you can download music for offline listening. Wouldn't that be putting music files in your storage...creating a music library? I have had itunes and rhapsody, both of which you can download music files into your computer. Surely there must be others you can do the same? Thanks for any advice
128x128easola01
Okay Elevick! Well, I guess I can use itunes to build a library. There is one big problem for me. If the files are asc, how do I apply good metadata to the tracks that will give me good cover art? Thank you
I have been a convert to Tidal for the last year or so and all I can say is ... should have done it sooner!

As long as you have a paid subscription (9.99 or 19.99 for hifi) you have access to so much music it is incredible.
Downloading it to play offline is ridiculously easy although obviously it takes up storage space on a phone say, possibly a tablet may be better?

I did try Spotify and I guess I just got so used to Tidal I found its interface and search and play functions to be a little clunky although it seems the majority think it is Tidal that is inferior...lol go figure.

Do not even start with the huge debate raging over Tidal available MQA files, all I know is to my ears the sq is noticeably superior. 
Okay, getting closer to figuring this out. Getting maybe 2 services to provide different functions and greater selection is very appealing. It looks like tidal and deezer elite are great choices for streaming...SQ and all. But I would like to do my offline listening through my computer. Tidal...I don't know about deezer...only goes to your phone or tablet for offline listening, so does spotify go to your computer for offline listening? If I have to give up SQ to do offline through computer I will. 

As I said before, I can do this with itunes, but as I understand it AAC files are no good for metadata? Spotify does mp3, and that would work for metadata provided I can play through computer. Any suggestions? Perhaps a music subscription/streaming not mentioned?
I'm looking at the Spotify app as displayed on a MacBook Air.  Downloaded albums are listed under "Playlists".  When I turn WiFi OFF, these are still available and playable.  I expect something similar will be true for Tidal as well, just haven't tried with it. 
Tidal states offline is only on smartphones and tablets...but your spotify goes on to your computer for offline listening?