Gratitune is an excellent way of discovering new music through your emotions and moods, you will find good music resembling to your mood.
Only suggestion i have is to diversify it into making it more useful.
a useful addition could be to use the prompts to understand why they are feeling a certain way, and then provide them with some call to action on what they can do next to improve their emotions. For example, if a person is feeling very unhappy and sad, and he selects to write a gratitude prompt, after he finishes that, they are provided with a list of things they can do to deal with that situation, it may be trying to resolve whatever was bothering them, etc.
Congratulations, everyone! It sounds like you have a fantastic product. To make it even better, consider improving the UI/UX design with a more subtle approach. Also, adding more playlists directly within the app, rather than redirecting to other platforms that might show ads, could enhance the user experience. Great job overall, kudos to you all!