DOOGEE DG800 Unlocked 4.5" IPS Screen 3G Smartphone Android 4.4.2 MTK6582 Quad Core 1.3GHz Dual SIM Wifi GPS 8.0MP/13.0MP Dual Cameras (Black) Dual SIM Card Dual Standby; 2G: GSM 850/900/1800/1900MHz 3G: WCDMA 2100MHz OS: Android 4.4.2 RAM : 1GB ROM : 8GB 8.0MP front camera , 13.0MP back camera with flashlight and auto focus Supports WIFI,GPS,A-GPS,Bluetooth, OTG, G-Sensor and etc 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.