I've asked around and this seems to be a bug with the iOS app. I'll forward your post so this can be looked into.
In the iOS app it only lets you send songs to users who have connected their Spotify account to Facebook. Even if you connected to Facebook, you won't be able to send music to a user who has not connected to Facebook. So whether you connect to Facebook or not, it still doesn't work properly.
However, sharing songs does work in the desktop app. You could try using to desktop app to share songs for now. Right click a song and click on "Share" ---> then clck on "send to".
MattSudaRock Star 24
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