Tidal, Deezer

My whole family uses Tidal a lot.  The sound quality is great and they have a fairly good selection. 
I "off-line" a lot of content.  It is stored on your phone but you need Tidal with a valid subscription to listen.  It's really easy to download music.  When you find a song or album or even a playlist, you will see a little toggle to click to off-line the music.  You can even create a playlist and off-line it.
So, why off-line it?  I download the data via wifi which doesn't use data and is usually faster.  That way when I'm driving or flying I have a library to listen to that doesn't need an internet connection.  And to be honest, Tidal can be quirky and not always get a good connection.  Having music store on my phone helps to avoid interruptions.

to answer some of the questions:
Metadata-who cares.  I'm listening, not looking
Why download/offline-I travel a heck of a lot.  Can't get data at 30k feet or when driving in the back country.  Also, my turntable doesn't work in my car.
Quality-it's quite good.  Remember the limitations in car audio or $200 headphones.  At work I have a nice system and actually stream tidal through my Chord Hugo and it sounds very nice.  Yes, I can get better resolution at home with my main system but my turntable works fine there.
Finally, I like playlists, either streaming or offline.  Sometimes I'm lazy or preoccupied.