I've read a lot of confusion and experienced some of it on my 2015 Countryman and Mini Connected, especially regarding Spotify and Pandora through the Mini display. Even the dealership was telling me I didn't need the cable even though you do because you can't control those apps through bluetooth and have the full display and you get no sound just using the lightning cable even if you connect a separate aux cable from your phone to the Mini. Yes you can just use bluetooth but the sound and display are blah and can't control the app through Mini Connected. I solved it and sorry if someone else already did but here's what I found using my iPhone 6s:
I bought this cable from Amazon http://amzn.com/B00WAT3Z7E, it has USB connector, two aux connectors and a lightning connector. This cable was only $10.98 compared to BMW/Mini cost of $95. You connect one aux to your phone and one to the Mini aux connector. You connect the USB to the Mini and the lightning to your phone. You need to download the Mini Connected app and you'll need the Spotify and Pandora apps respectively. Once you start your car (or acc power) you start the Mini Connected app and it'll connect to your car. Then toggle Mini Connected on your car and go to the Mini Connected icon and scroll down to other apps, you'll see Spotify and Pandora, select either one and if the app isn't already turned on, your phone will tell you Mini Connected is trying access it, then tell it ok. And there you have it, you can see Spotify or Pandora on the Mini display and you can control them via the control stick. More importantly you have sound! In my opinion it sounds great, no distortion and very clear. I love it!!

 

AWESOME, i have been having the same problem and its driving me nuts! i just didnt want to buy the expensive cable, i'll have to order this now!

Thanks!