<p>It's sending songs or at least portions of songs to your contacts via a smartphone app. Think WhatsApp, but instead of sending someone a text message, emoji, picture or sound clip you've just recorded, you can send your new favourite tune.Can't I already do that with existing apps like Spotify and YouTube?</p><p>Sort of. But a new batch of apps is set to deliver a much richer, more rewarding experience than simply clicking a button to send a mate a link.</p><p>Stereotypes (available now on iOS) for instance, allows users to form groups to share music and comment on individual songs. Songs are currently sourced from YouTube, with SoundCloud and Vevo are being mooted as future additional options. Users can log in using Facebook, which makes building groups with friends a simpler process, and collaborative playlists can be built through messaging.</p><p>Stereotypes has a (somewhat unnecessary, we feel) premise that the user "be a VJ" by answering questions such as "What song will you let loose to this weekend?" and by filming self-shot video intros in which they explain their choices to camera. But still, an intriguing app.Any others?</p><p><a href="http://www.stuff.tv/music/next-big-thing-music-messaging/feature">Keep reading...</a></p>