If you are keeping the same line and just activating the iPhone in place of the LG the fastest way is to call Verizon, or you can try via My Verizon and your accounts/device page. Remember though, in the future if you want to Edge early or make any changes to your account that require return of the LG phone you should consider what you do with that phone until then. From what I understand, voicemails will be lost when you change from an Android to an Apple and vice versa. There could be other unwanted or unexpected changes as well. I'm sure others will chime in with information as well.
