OnSong added Spotify Integration in OnSong 1.999 in late October 2015. While the SDK was in a beta state at that point, it appeared to be solid and worked well for more users. However, over time, the Spotify Integration for third-party apps has become less and less supported by Spotify. Spotify has very recently launched a new series of frameworks and is no longer supporting the older model of their services. This requires a big change in the way OnSong handles Spotify content and we are actively looking at ways to roll this feature out in future updates.