Sorry, this is a repost, don't know how to move it. Think this is a better forum as it is a general question... I have a d1 with 16g card, my son has a d2 with 8g. i have lots of programs and pictures on the card from the past 16 months, the d2 is pretty new. My son wants his music on his phone, its more than 8g, I have just about 10 g free. So we can swap cards. but I have about 25 directories with stuff starting with .androidsecure that looks to a bunch of .asec files, then amazonmp3, android, astrid, boos, data, dcim, dictdata.... nitrodesk, noteeverything.... I was hoping not to lose everything on my card. He just has his music on his card, so that can get reloaded on the new card. How do I go about swapping cards. Do I format them first, and if so, do I do that on the computer, or is there a way to do this on the phone? I noticed that dcim .android directories are on all android cards. (dcim is on cameras i know), but does android write them when you first mount the cards? Can I format his card, (how is the best way to do that), and just copy my entire card to his, and plug into my phone and I will have all my programs and data? Then format the larger card , insert in his phone and install music?