Re: can i use my old simcard on an unlocked phone....?
The RAZR Maxx uses a micro sim card if i am not mistaken. If you have a micro sim card, then yes it should work. You may need to change the APN on the phone to get on the internet but do that if it is needed.
If you have a regular size sim card, then you will need to buy a micro sim card which costs $9.99+tax and activate it on your account. That is the only way it will work.