T-Mobile
2G 1900
3G 1700/2100
AT&T
AT&T is using 1900 MHz (850 MHz in some markets) for 3G. T-Mobile will use 1700 MHz for download and 2100 MHz for upload (maybe I reversed T-Moble's bands.)
SKT
2100
iPhone 4s
UMTS/HSDPA/HSUPA (850, 900, 1900, 2100 MHz);
iPhone 3gs
UMTS/HSDPA (850, 1900, 2100 MHz)
Huawei e585
UMTS 2100 MHz
EDGE/GPRS/GSM 1900/1800/900/850 MHz
Novatel 2372
Tri-band HSUPA/HSDPA - 850/1900/2100 MHz
Quad-band GPRS/EDGE - 850/900/1800/1900 MHz
