As a social media editor, I deal with many accounts and different on platforms. Spotify is one of them. If you could just add a 'switch account/add account' section, it would be amazing. Normally, I use family plan. I think this idea can be applied to premium, family etc. paid accounts. Amount of the accounts can be limited to 5 for beginning, I leave it to you dearest developers.
I also think that in addition to the menu button on the side of every song, simple and frequently used commands like add to playlist etc. should be reached by swiping the song left or right as little square boxes.
And last but not least, there should be a section that we can see friend activities on mobile.
These are my ideas as a loyal user, I love Spotify. Hope there is a way for these updates. I think all the people out there improving this app is amazing.