I don't understand the point of this. It seems to be 99% the same experience no matter what you do and the only thing to really do in the experiene is try and guess a 4 digit password someone else made and to create your own 4 digit code for some one else to try and guess?
I can't understand why everyone else seems to think this is amazing when it seems to me anything but.
I can only imagine the other posters have never played a puzzle or a computer game as if you have experiened either this is utterly forgettable.