Nokia Lumia 830 Unlocked GSM 4G LTE Windows Smartphone w/ 10MP Camera - Green Display: 720 x 1280 pixels, 5.0 inches (~294 ppi pixel density) Internal Memory: 16 GB, 1 GB RAM Camera: 10 MP, Carl Zeiss optics, optical image stabilization, autofocus, LED flash CPU: Quad-core 1.2 GHz Cortex-A7 GPS: Yes, with A-GPS, GLONASS, Beidou Unlocked cell phones are compatible with GSM carriers such as AT&T and T-Mobile, but are not compatible with CDMA carriers such as Verizon and Sprint. This cell phone may not include a US warranty as some manufacturers do not honor warranties for international version phones. Please contact the seller for specific warranty information.