4S-н spec-ийг уншиж байхад GSM, CDMA аль алинийг нь дэмжинэ гэсэн байна лээ тэгэхлээр ямар ч 4S (ат&т, Sprint, Verizon) авсан gevey sim,unlock хийгээд Моби, Unitel-д барьж болно гэсэн үг юм байна
Cellular:
Technology CDMA2000 1X / GSM / WCDMA (UMTS)
Band WCDMA (UMTS) / GSM 850/900/1800/1900 / CDMA2000 1X 1900/80
World Mac-д
When Apple released the Verizon iPhone 4 in February, the iPhone 4's product line got a little more complicated. Because Verizon’s network in the U.S. uses a different wireless standard (CDMA) than AT&T does (GSM), Apple had to build different chipsets for each network, and thus, different phones. But the iPhone 4S changes all that:
It can access either the CDMA or GSM network, depending on which carrier you sign up for.