Old thread I know, but I searched for this - I don't know if the old 2007 iDrive is different to the new one in this respect, but I just tried Spotify on my iDrive and the track buttons work and it shows the track title on the screen.
I wasn't expecting it to work but was pleasantly surprised when it did! No Jailbreak, just connected with the standard USB Y cable. Brilliant!
F82 M4 Coupe (Black Sapphire, Sonoma Beige)
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