This review is to help compensate for the people who leave a review stating that this app doesn't work. I'm sure they can't help it that they are too stupid to know better. Given the state of our education system, we are lucky they can string together enough words to make a sentence.
The whistles are in a frequency that can not (usually) be heard by the human ear. That's why it's called a dog whistle. Furthermore, those who are expecting their dog to come running or perform other behaviors, fail to realize that dogs need to be trained to respond to sounds. Dogs don't really understand the alphabet and language they are responding to the sounds of words.
Show less