It is surprising that this app can mistake the human voice/whistles for some birds (try hooting like an owl or whistling like a sparrow/starling)!
[1] http://atcnetz.blogspot.com/2019/02/arduino-auf-dem-fitness-...
[1] https://ieeexplore.ieee.org/document/1203230
[0] https://www.nobelprize.org/peace-prize-documentary-films/ [1] https://youtu.be/UsqKz1hd_CY
It is surprising that this app can mistake the human voice/whistles for some birds (try hooting like an owl or whistling like a sparrow/starling)!