I love the idea of One Calm. Sometimes I dont find the time to fit in an entire meditation session and sometimes can get overwhelmed with the stresses of the day so being able to whip this out and assist in calming me down will be a great tool.
I downloaded the app and gave it a go.
I love the way you have integrated interactivity into the session, which forces you to pay better attention to the app while you are doing it. That's cool.
I'm sure English isn't your first language so I would maybe suggest you use ChatGPT to help you with the copy for the app. The onboarding text and the start up text could be improved a lot for clarity.
Overall though great job! Think its a fantastic idea and looking forward to using it myself.