Based on the definition you provided I do believe that the app your team developed in capstone is considered to be a mobile medical app. Your app allows for a mobile user to check their auditory cues and identify which sounds frequencies they can or can not hear. This app allows the user to check their hearing without the use of the Audiometer medical device. The app might not be as accurate as an actual medical device which test auditory cues but it can be used as a regulated medical device.
A mobile medical app that I found online is called “instant blood pressure.” This app allows a mobile user to read their blood pressure in 35 seconds. The user simply places their right index finger over the lens of the camera and holds the phone against their chest to get estimates of their blood pressure. Their is also another app called “instant heart rate” which identifies your heart rate by placing your finger over the camera lens on your phone. These two apps act like a sphygmomanometer and ECG, respectively.

https://www.instantbloodpressure.com/
https://play.google.com/store/apps/details?id=si.modula.android.instantheartrate&hl=en