How do you convince your parents to let you get a new mobile phone even when you'll buy it yourself?

Hiyaa , i got the phone i wanted the other week, all you need to do is drop hints, and say how cool it is and that every one is laughing at how rubbish your one is now, i got the iphone touch, and all i had to is ask butthen again i am famous, i am not telling you who i am but it has just been my birthday.