Harken

Main Features and Characteristics:

1. Playlist Rewind: If a user liked how a playlist was last week, Harken can restore that version for them.
2. Daily Changes Report: Users can see all the additions and removals made per day, every day for every playlist they track.
3. Playlist Analytics (Coming Soon): Allows users to know which songs come up the most in their playlists.

Target Users and Core Advantages: Targeted at Spotify listeners, especially those who listen to 'made for you' auto-shuffling playlists. The core advantage is solving the problem of lost songs on Spotify—when users forget to take note of a song they like and it gets removed by the auto-shuffle, Harken finds it for them.

Usage Flow and Pricing Information: Users can join or sign in to use the service. Harken offers a Free tier to get started, which allows users to track 5 playlists, see unlimited daily changes, and access Playlist Analytics. No other paid tiers or pricing models are mentioned on the page.