We don’t collect any of your personal data.
All data used for authentication is used solely for connecting to Jellyfin instance you provided. Application doesn’t store passwords in any way, only the access token it received from the server.
All your actions (toggling likes, switching tracks, etc.) are only visible to the instance you connected to. Discrete doesn’t track anything in any way.
If you want to delete your data, you just delete the app from your device.