Is it possible to use both a 3gs which as the old sim in it with a iphone 4 with the new sim with itunes? Been toying of keeping my 3gs and by one of those ihome like docks that let you plug you phone into it and play music. My thinking is as more iphone 4 are sold, especially the white, these devises that can be used with 3gs but not iphone 4 might come down in price. Just dont want to mess up my phone. Thanks for any information. Sorry thought I was in help area. I know asked in wrong area.