Definately iPhone 5 !

After bought it since launch day, I still think its the best eventhough I have other Android phone to play with. The screen, camera and everything.

Few days back I go machines and I play with 4s awhile (dont know why they didnt replace 5 with it).

It felt bulky, heavy, just doesnt feel right! You should put both on your hand to feel the difference. Btw, I came from 4S as well.