iPhone data connection types
On GSM (All but Verizon/Sprint):


4G = LTE (or HSPA+ on AT&amp;T)
3G = UTMS/HSDPA
E = EDGE  
o = GPRS


On CDMA (Verizon or Sprint in the USA):


4G = LTE
3G = EV-DO
E = no equivalent - not possible  
o = 1xRTT