I have tried it... on my dog... doesn't care .... and on some stray dogs around my neighbourhood my opinion remains the same... DOESN'T WORK

Impossible for this to work. DOg wistle frequency is above 20,000 Hz which is way above the freqency response of the phone speaker. Even above the frequency response of the best home stereo systems.

[Kitzie]

"The frequency range of a dog whistle is largely out of the range of human hearing. Typically, a dog whistle is within the range of 16000 Hz to 22000 Hz with only the frequencies below 20000 Hz audible to the human ear"

Quote from: http://en.wikipedia.org/wiki/Dog_whistle

My dog doesn't seem to give it much attention but it's interesting to test what your high frequency hearing is like (and your friend's!). Personally, I can just about detect the sound up to about 18kHz, by which time, I can only JUST detect it and it is VERY directional. My young lad could hear up to 18.5kHz but my buddy who has spent lots of time around loud music could only hear up to 16kHz!
Like it was said earlier in the thread, the chances are that your speaker isn't actually capable of producing the frequencies stated in the software. The software is fun but don't take it too seriously.

[Kitzie]

Here's a picture of my dog and he can hear it fine
http://s3.amazonaws.com/readers/2008/10 ... ears_1.jpg