One thing is that the app is extremely buggy. I have a playlist with over 1k songs downloaded on it and have faced a bug where newly added songs on my playlist cannot be viewed or listened to through the playlist that I added them to---even though the app says that they have been added. Looking up this bug online reveals that multiple users have experienced the same issue, a little over a year ago. And the problem is still not fixed... Additionally, you cannot shuffle play your entire playlist.