Pandora never had an open API, but they had a web interface that could be parsed and replicated by 3rd party apps like pyRadio. Even when they required encryption for the stream calls, pyRadio could keep up with the key generations.

But a change made on Pandora's side in early January broke all that. It's always been a closed box, they just finally locked it.

No pandora app for anyone unless Pandora writes it themselves.