Are you able to put your already activated micro sim card in an iPhone 4?

Yes , i phone 4 want micro sim ,Because there are now several countries where the iphone 4 is sold unlocked, everyone can choose the best network and tariff for their needs while not tying themselves down to a long contract. There is no doubt that this is the way phones should be sold, however, buying the iphone 4 in this way has a distinct problem all of its own: the micro-SIM card.