yeah but but but but :D
Avicii is only programing the song , not sure what is that but i can tell it's different than Producing it .. and you can't tell if it's a duet song maybe some harmonizing or even a background vocals
that article in the Q Magazine said : HFTW / Fun / Everglow / AOAL / Up&Up are the best songs in the album
so far so good at least for me :D
they also said "Fun, featuring Tove Lo, is more moving than anything on Ghost Stories"
so it's all depend on Coldplay not the guest .. with all due respect to Tove Lo or even Cat power who sing " wish i was here " beyonce is a STAR and she easily can make a hit song if Coldplay want to