Swap Apple iPhone 4S 16gb Black for Samsung Galaxy S3 SIII .

Looking to swap my iPhone 4s for a Samsung Galaxy S3 or possibly HTC one X. My iphone is black, 16gb, boxed with all items, bought on vodafone and unlocked through them. Had screen protector on from day 1. Apple warranty runs out on 3rd November 2012. phone must work on vodafone or be unlocked. Txt please 9-5, calls after 5.30pm