Samsung i997 Infuse 4G, 8MP,16GB, WIFI, GPS, Super AMOLED Plus, Gorilla Glass Capacitive Touchscreen AT&T Unlocked World Mobile Smartphone 2G: GSM 850 / 900 / 1800 / 1900, 3G/4G: 850 / 1900 / 2100 (HSDPA / HSPA+) 4.5-inch Super AMOLED Plus Capacitive Multi-Touchscreen w/ Protective Corning Gorilla Glass Android v2.2 (Froyo (upgradable), 1.2 GHz Cortex-A8 Processor 8 Megapixel Camera (3264 x 2448 pixels) w/ AutoFocus & LED Flash + Front-facing 1.3 Megapixel Camera Internal Memory: 16GB storage + microSD Slot Expandable up to 32GB Unlocked cell phones are compatible with GSM carriers like AT&T and T-Mobile as well as with GSM SIM cards (e.g. H20, Straight Talk, and select prepaid carriers). Unlocked cell phones will not work with CDMA Carriers like Sprint, Verizon, Boost or Virgin.