Hi,
After getting a Droid Maxx, I popped in an Idea SIM and realized that it does not allow voice calls. That SIM was actually cut from a normal SIM. I tried the global mode and that has no option to select the network. So I tried the other mode (LTE/ GSM) and that showed me Vodafone and Idea, but nothing worked.
Then I manually put APN and data started working.
I tried a Vodafone nano SIM (again cut from normal) and that one got data working, but no voice calls, though network bars showed up fine.
I thought the cut SIMs are an issue, so I got a brand new Idea nano SIM and popped that inside the phone.
That one does not even allow data now. The phone just states No service.
I learnt now from a seller on ebay that the phone has to be activated on Verizon first. Then it can be used elsewhere.
I am not sure what exactly Verizon installs on the mobile.
But question is what can be done to unlock the GSM.
I don't have access to CDMA nano SIM's so I cannot test that out.