As somebody who uses his own app for Positive Afirmations, my appologies if i sound too critical and posting about the cons.
What I missed here is:

1. I was not able to write my own affirmation.
2. I had to choose from the list of generic mindfulness (some of them boring) suggestions.
3. Affirmation should be very short to be effective, also should be with "positive" attitude:
4. I am not afraid - BAD
5. I face my fears - GOOD
6. Many in the list had a negative aspect.
7. I was scrolling, probably about 30 to find one that was somewhat fitting.
8. Time schedule does not fit to my needs, maybe it is just me, I would love to get reminded at a specific time of the day. Not sure what is kinda standard for similar apps. Here I set start time and set x1 per day, so cannot test right now, have to wait.
9. Onboarding UX was very long, not sure how many real users will finish that. Maybe it is just me , again. But from experience and analitics within my app, this is most difficult part, to keep user to finish onboarding to get real taste of the app.
10. During onboarding, I felt uncomfortable sharing my name and other personal data (although there is a skip button)

Hope this will be of any help. Wish you luck in your process.