i don't know how jailbreaking and unlocking an iphone 4 works. if i buy the iphone 4 unlock and jailbreak it, can i keep my existing phone number from verizon? what will i pay monthly for the service? will verizon know that i am using an iphone and charge me for data service? any and all info would be so helpful. basically i want an iphone but dont want to pay the huge monthly service cost!