Inception App for itouch?

okay i don't ******* get this dumb ****, i looked that the reviews for the inception app and literally everyone was saying it was really good, i download it and it said plug in your headphones, and tap to start, then it say's that it does different things like if the sun is shining, if you're walking, if you're quiet, etc. so i plug my headphones in and shake the itouch around and it says "it is quiet, inducing Quiet dream" and it Just sits there and says inducing quiet dream and nothing else happens, no sounds or anything, anyone know what is wrong or what i can do to make it do something?