I've been an AT&T customer since the Cingular days but have been thinking about switching for a while. My father in-law works for Verizon which gives family members a hefty discount so we're thinking of switching to them and their unlimited plan. The problem is my wife got an AT&T iPhone 7+ in December (on the Apple installment plan) and I know that phone won't work on Verizon's CDMA network. Luckily I still have my 6S+ which, from what understand, should work fine. My question to you good folks is what are my options here for my wife's phone? Is there any kind of trade-in program for Verizon or Apple where they'll swap her phone with a Verizon-compatible one? Do I have to just sell it on the open market and pay off Apple? If the latter, is the phone locked at all? Thanks!