After trenchant negotiations with record companies and much hand-wringing from impatient audiophiles, the Swedish music-streaming service Spotify launched in the U.S. last month. With more than 13 million immediately accessible on-demand songs, mobile capability on most smartphones, a no-charge honeymoon period, and seamless fusion with Facebook, Spotify has been heralded as the "iTunes killer" and might just be the thing that lifts American listeners up into the cloud. "The response has been overwhelming," says Daniel Ek, who helped launch Spotify in 2008. An early adopter of Napster, Ek realized that BitTorrent, subscription, and piracy sites overlooked the fundamental fact that listening to music is both a personal and a collective experience. "Music is the most social thing there is," says Ek. "We wanted to set it free and see what happens." Supplanting the need for a recommendation engine, like iTunes or Pandora, Spotify displays what people in your social network are listening to, shares playlists instantly, and offers offline access. An "inbox" feature even allows you to send specific songs to a friend or, say, a significant other, as one European man did to propose (his chosen song titles spelled out "Will you marry me?"). "It's been interesting watching people wrap their heads around Spotify," says Ek. "They're still discovering new ways to use it."

Details' editors curated four playlists from Spotify's vast catalog—one for each essential soundtrack-worthy occasion.

COCKTAIL HOUR
Play time 33:36
Two parts funk, one part jazz, a dash of French—stir and sip.

"Ford Mustang" Serge Gainsbourg
"New Beat" Toro Y Moi
"Doralice" Stan Getz
"Shooting Holes" Twin Shadow
"Afro-Harping" Dorothy Ashby
"100 Days, 100 Nights" Sharon Jones & The Dap-Kings
"Hot Pants, Parts 1 & 2" James Brown
"Can't Hear My Eyes" Ariel Pink's Haunted Graffiti
"I Fall in Love Too Easily" Chet Baker

WORKOUT
Play Time 32:54
Let Iggy Pop and Justice unleash the beast in you.

"Signature (Thomas Bangalter Edit)" DJ Medhi
"Tightrope (Feat. Big Boi)" Janelle Monae
"Fuckin' in the Bushes" Oasis
"One Life Stand" Hot Chip
"Civilzation" Justice
"Search and Destroy" Iggy Pop
"I'm Good, I'm Gone" Lykke Li
"Hammertime (Home Depot)(Feat. Big Freedia)" Monsta wit da Fade

ROAD TRIP
Play Time: 33:22
Rock and roll—fast or slow—was made to be heard on the road.

"Desire Be Desire Go" Tame Impala
"Hold Tight!" Dave Dee, Dozy, Beaky, Mick & Tich
"Taken for a Fool" The Strokes
"California Soul" Marlena Shaw
"Courtesy Laughs" Phoenix
"Not in Love" Crystal Castles
"Piss Factory" Patti Smith Group
"Master of None" Beach House
"Gut Feeling (Slap Your Mammy)" Devo

DANCE PARTY
Play Time 40:53
When Spank Rock, David Bowie, and the Beastie Boys tell you to get up—you get up.

"Sweet Talk" Spank Rock
"Call Your Girlfriend" Robyn
"Black and Yellow" Whiz Khalifa
"Make Some Noise" Beastie Boys
"Electric Feel" MGMT
"Power" Kanye West
"Kim and Jessie" M83
"Ce Jeu" Yelle
"Let's Make Love and Listen to Death From Above" CSS
"Let's Dance" David Bowie

Play Now
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