Sharing a song in Spotify with non-Facebook users (mobile)

[user-removed]

I can't tell from reading on there whether I am doing something wrong or if spotify simply doesn't support but . . . On my iphone 6 (running Ios 😎 I am logged into my account through Facebook.  I have a friend who is not logged in through Facebook but has a profile in spotify.  I've located his profile and follow him.  He is able to use the share function to send me a specific song but I cannot do the same.  When I use the share "Send to . . . " button it pulls up a handful of my facebook friends but not him (he is on facebook and I am friends with him but he doesn't appear in my list to choose from).  I also can't find his spotify profile even though, as described above,  I follow him and he can send me music.  I've read things on various boards/forums about adding him but I already follow him and can't figure out any other way to add him to the list.  Am I missing something - very frustrated. Oh, also, I can share music or do what I am describing above on the desktop application just not on my iphone . . . what gives??