The iphone 4 comes with a micro sim. Your normal sim will not work with it. My AT&T dealer says he can transfer data directly from your sim/old phone to your new iphone 4.
You can fit a SIM card from your HTC Wildfire to an iPhone 4 by using the SIM port included in the iPhone.
No!
You have to put a small tacking chip in the sim card and download an app on your 4s to track it
Yes it can be swapped. I actually swapped my razr's sim card to my iphone. Nothing happened. It works perfectly.
No
If your 3GS is locked, you can't insert a SIM card.
Yes, as long as your with the same service provider. It also has free Wi-fi. Unlike the "Blackberry" you can just put in your old Sim card and it should work just as well.
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.
any AT&T phone that can take that sort of sim card.
First off I'm assuming you meant iPhone 4, not 4G (common mistake). And to answer your question, no. The iPhone 3G has a much larger sim card than the iPhone 4, but you can just take them to At&t and they will transfer everything to the new card for you. If you already have both phones, I doubt they will even charge you.
Yes the iphone 4 uses whats called a micro sim card it is smaller then the regular sim card out there. At www. phonetraderonline.com they can custom cut your existing sim card or provide you with a micro sim for your carrier.