I searched for you and from what I've read iPhone 4 on Verizon runs on Qualcomm MDM6600 chip which is the same as some other Verizon phones but the Verizon phone cannot be used on a GSM network, as it lacks a SIM card. The Verizon phone will only work on CDMA systems not only due to the lack of a SIM but also because of the antennas. It supports two cellular frequency bands, while Apple supports five bands in the GSM version.