Pretty sweet – Tone Generator: Audio Sound Hz Review

This is a pretty sweet app. It’s cool that it can test how low and how high your ears can hear. But I have a question, why do all apps like this only go down to 20 Hz? Why don’t Apps like these go down all the way to one Hz? Maybe have a countdown from 20 Hz to 1 Hz.
Review by mr. Analyzer on Tone Generator: Audio Sound Hz.