apple iphone 4, 2 months old unlocked , swap for samsung galaxy s2 or for sale ?

this is my iphone 4 unlocked 16 gig in black which is 2month old! reason i am selling this phone is that im after a samsung galaxy s2!! will be happy to swap this iphone4 for a samsung galaxy s2 or for sale for 210! txt me if interested on 07934733983 , cheers