What phone is better to get, the iphone,blackjack, or palm from at&t

my dad is getting me a new phone around november and december so when my upgrade comes for my phone, i can use it. which phone is better though? which one will be easier to use and figure out for a 15 year old? is the iphone, the blackjack, or is the palm phone better to get from at&t? please help me decide, thanks!!!!!!!!!