I want to transfer to Verizon from Sprint but keep my phone?
It's awesome that you're looking to join the Verizon family tbacon! As Elector stated the device is unable to be used on our network, however you can trade it in to receive a Verizon Gift Card and purchase a compatible device. For all the details, please visit http://bit.ly/1i1vrCu AshleyS_VZWFollow us on Twitter @VZWSupport
Not possible
Although they both are CDMA I believe a Sprint phone just works on Sprint.
I have read here on the forum that a Verizon iPhone can be used with limited capacity but don't quote me on it.
Good Luck