Soundrop is one of the few dozen apps built specifically for the new Spotify app store.
The startup has pioneered the concept of "listening hangouts", involving users gathering in virtual rooms to listen to music with other users from around the world.
Soundrop rooms are typically indexed by genre and play music selected and voted for by the users, with songs moving up in the queue depending on how many votes they get.
The app also hosts artist-branded rooms for the likes of Carrie Underwood, Kelly Clarkson, The Smiths, Sebastian Ingrosso, Carl Cox, Sigur Rós and One Direction.
In May, Soundrop claims that it had 3.3m listening sessions in more than 7,000 listening rooms, consuming in excess of 60m songs.
Northzone has been suitably impressed by Soundrop to invest $3m in the startup.
Soundrop will now form part of Northzone's growing digital music portfolio, which already includes Spotify, digital label X5 Music and media player doubleTwist.
Torleif Ahlsand, from Northzone, will join Oslo-based Soundrop's board of directors as chairman.
Ahlsand, the general partner in Northzone, said: "We're big believers in services that are social and scalable by design, and on top of it are helping enrich the music ecosystem.
"Soundrop builds brand value and consumption opportunities for artists and labels, whilst creating a more fun listening experience for the consumer. It's a win win situation for all."
Inge Sandvik, the co-founder and chief executive of Soundrop, added: "Social applications will transform the way we experience music on our laptops, on our phones, at a concert or at a bar.
"Soundrop is already making it easier to discover, experience and share music with your friends. Now we're pleased to accelerate our growth with Northzone's support."