Vince Pope's soundtrack for the episode uses a low piano score for most of it, and it has a sad, yet somewhat calming feeling to it. No song encompasses this conflicting tone used to excellent effect more than Jump, which plays during the heartbreaking climax of the episode. The piano, the odd digital sounds, and what sounds like white noise if it had a tone all lend themselves to a breathtaking song.
Radiohead's "Exit Music" scores the end of the episode. Fittingly for an already bleak episode with a last minute twist that darkly recontexualizes everything that came before it, it repurposes the song's defiant, Together in Death ending as a mean-spirited middle finger.
Has Belinda Carlisle's "Heaven is a Place on Earth" ever been more heartbreaking or appropriate?! Charlie Brooker has understandably said he would have been devastated if they hadn't been able to use it.
Clint Mansell composed 10 original songs for the episode, on top of all The '80s hits that are included. And they range from heartbreaking to chilling to heartwarming. What a soundtrack!
Nearly all of those songs make it into the episode, with Netflix apparently burning money to get only a few seconds of a Prince song for it.
Even if they weren't in the episode, the ones that inspired scenes are pretty epic if you just... play it in the background yourself. Say what you like about the Internet being bad, Brooker, it has certainly given multiple ways to watch a pretty epic episode.
"Fall into Me" by Alev Lenz is kind of like a haunting romantic death song, and is used as the ADI bees slowly wake from their hives and start flying around the country. The scene with the images and the song seems pretty bittersweet, as if the movie is over and the country is turning peaceful. Nope, because we all know those bees are about to go on a murderous rampage and there's still fifteen minutes left. The scene is really nice, but made sweeter with its irony.
Playing the outro of The Smiths' "Panic" as the episode outro was an excellent choice, both in linking to the episode (it says to hang the DJ because he claims to know you and play songs you like but doesn't really know — change songs to relationships), and in generally being an awesome rock tune that got introduced to an international audience (it's popular in the UK, but its Listing Cities lyrics hasn't given it much exposure abroad).
The episode was scored by Alex Somers in collaboration with Sigur Rós. The whole soundtrack is beautifully ethereal and lends to the dream-like feel of the episode, but special mention has to go the track named End, which Sigur Rós later released as a single.
Who would've thought "Relax" would be used in a franchise like Black Mirror? It's oddly apt, too, for Stefan and his love/hate relationship with drugs, as well as the different relationships between drugs and him feeling relaxed. And he really needs to relax and not do it.
"O Superman", the background music in the ending sequence if you choose to let Stefan go on the train with his mum - at this point, knowing he will die.
"Hold Me Now" by the Thompson Twins is one of the options you can have Stefan listen to on his Walkman while riding on the bus. Can't be any more 1980s than this awesome song.
"Making Plans for Nigel" straddles the line between being hypnotically awesome, deliciously cheesy, and surprisingly apropros.
The ending song "Not One Minute More" by Earl Grant is a jazzy romance song that at ear may be Soundtrack Dissonance—it plays over the Bittersweet Ending showing that Theo and Danny's marriage is permanently fractured because Danny couldn't let his and Karl's flings go, and now Theo and Danny are cheating on one another by agreement. However, even though it is technically a romance song, the lyrics tie into the plot nicely. The singer is basically saying that he'll love his sweetheart until "the sun gives no light as before [...] not one minute more." Basically, he'll love her forever, but the delivery of the chorus makes it sound like it's only temporary. This is a pretty good descriptor of the final state of Karl and Danny's "relationship": they'll always want one another, but will never outright face the issues their relationship has, so they'll continue writing it off as nothing more than a yearly hookup.
Andy Williams' "Can't Take My Eyes from You", which pops up several times through the episode, is another invoked use of Soundtrack Dissonance. Outside of its deliberate contrast with the final scene—specifically, the Ambiguous Situation of which person in the car was shot and killed—the song provides two other links to the episode's plot. The first is that it's a longing love song, fitting considering Chris' fiancee's death is what kicked off his whole downhill spiral. The second is that not only was not being able to take his eyes off his phone the reason that Chris crashed the car and indirectly killed said fiancee to begin with, but Chris's whole point about everything was that people are unable to take their eyes off their phones, no matter what is happening.