This is an application that serves solely to test the user's hearing at different audio frequencies. At the end of the test, the chosen volumes are displayed.
Before taking the test, adjust the device volume to maximum. It is interesting to test in a silent environment.
This is a basic test, it will never be able to replace an exam taken in the office.
Here it is possible to make a relative analysis of the user's hearing, but it is not possible to obtain absolute values in dB, as cell phone headphones were not made for this.
Remember that each cell phone has a specific equalization, while each headphone has a different frequency response.