I'm a doctor working in London UK and Lungy is my first app. I started working on it during COVID, and it has just launched on the app store. Lungy (https://www.lungy.app) is designed to make breathing exercises much more engaging and fun, initially for stress and anxiety, and then eventually, hopefully for people with breathing problems such as asthma, COPD and long COVID. Lungy includes real-time cloth, fluid and softbody sims running on the phone's GPU and also generates music with a sequencer and polyphonic synth. Everything is generative, so the whole download is < 50MB.

Would love to know what you think and very happy to answer other questions. Thank you!