Ha. The Android check box didn't prevent Spotify streaming over 3G. So Android's either broken there or Spotify gets around the setting somehow.
It would be nice if the Spotify app could either have a setting for disabling streaming over 3G or pop up a warning when you attempt it. Perhaps each time the play queue goes from empty to having something in it (so not every time something is added to the play queue).
Awesome work by you :)
Background connections are used for some things you can turn off in the spotify settings - scrobbling to facebook and last.fm and the push notifications but it does also send usage stats from time to time. The only way to stop this would be to turn off mobile data on the phone.Overall, I think you have it pretty much under control now. It does seem a pity that we can't just have the equivalent of an aeroplane mode button in Spotify though.
Thanks for your patience - have a great New Year!