"The main issue behind it was a way to connect people subtly, without being intrusive," said Bassoli. "And music is the way teenagers want to open themselves to people around them." When alone, a tunA-enabled device functions like a regular MP3 player. But around others like it, the interface displays other in-range users, identified by the avatar of their choice. Avatars appear or disappear automatically as users go in and out of range. Clicking on others' avatars lets you see whatever personal information or messages they want to share with the world. It also displays their playlist and the song they are listening to at that moment so you can decide if you want to tune in.