I know that on VZW you have the sim card for a 4g phone with the sim card being unique to your phone #. And that the card you can take out of one 4g phone and put it into another with VZW. I am getting the Galaxy Note 2 and doing an alternate upgrade. I read that the sim card is embedded and you cant take it out. Does anybody know how Sprint handles their activations for a 4g device?