There's lots of buzz about Forgotify (http://forgotify.com) - a tool, that crawls Spotify against unplayed tracks.
Non-technical press articles say that they use Spotify API to crawl the songs and index only those with zero play count.
However, according to Spotify API documentation, such value is not available for single tracks:
https://developer.spotify.com/docs/apps/api/1.0/api-models-track.html
Similar question about possibility to retrieve track play count has also been answered here on StackOverflow (Get play count of a track from Spotify API) with similar results - that it's not possible.
I'm looking for a clue how Forgotify achieved what they claim they did. Any ideas? :)