Um actually All Verizon phones operating on the Verizon network are operating on cdma all the time. All calls and sms occur on cdma. This is why voice always works on 4g phones. No carrier is using voice over lte. Data can go either way but follows voice service. If the phone is on gsm for voice, data follows. If there is compatible lte, data could use that too.
Razr Maxx HD BL Unlocked, Rooted Bionic GSM enabled, Stock Razr, Eris 2.3.5 GSB, Inc2 Froyo, 1.2Ghz Droid X Koush recovery, Rooted Fascinate, DIs, Ally, Charge.