Ever wanted to have a siren on your phone so that when you are at home, and something strange happens, you could use it to scare bad people? You can plug your phone to larger speaker and get a real siren sound.
It has several sirens sounds such as fireman siren, police siren, prison siren, and many others.
Since the phones speakers are not too loud, plugging your phone to a amplifier, such as the cars one would be better.