When playing a song on my android (4.4.4) phone, I do the following:
1. click the "..." button next to the title
2. click Share
3. pick Hangouts and the person and send
4. the friend gets a link, e.g., http://open.spotify.com/track/2WRzpLD8qDRrxMXc63E5WJ
If I click the link, it goes to the song and it plays fine. My friends on iphones click the link and it goes to the album and no song plays. In the reverse situation, when they share a song with me, I get a better message and a working link. e.g., "Listen to ABC Artist * Album Spotify: http://linkabcdefg"
It'd be great if this got addressed so android sharing had nicer messages and worked correctly on iphones.