Use Eris without Verizon service?

[shadowhawk2021]

My brother is loojking to switch from an iphone to the EVO, but he wants to test a couple of apps before the switch. I was letting him use android on my TP2 but it has no sound. He can get ahold of an Eris that is not active, but he wants to make sure that if he turns it on and uses it over WIFI to get apps the owner of the phone won't get charged for service?

Probably a dumb question, but figured I would ask before I tell him to do it.

Thanks,
Shadow