That depends on which carrier you’re using. Different carrier networks use different technologies for connectivity, and these technologies vary by region and country. Because each network is different, your device may not work across all carriers, or certain features may not work well (if at all).
NUU unlocked Android smartphones are compatible with major North American carrier networks, including T-Mobile, AT&T, Allvoi Wireless, Beast Mobile, Best Cellular, Boom! Mobile, Boost Mobile, Boss Wireless, Consumer Cellular, EarthLink Mobile, Gen Mobile, Google Fi, GoSmart Mobile, Hello Mobile, Kroger Wireless, Lycamobile, Mango Mobile, Metro By T-Mobile, Mint Mobile, Net10, Optimum Mobile, Patriot Mobile, Red Pocket Mobile, Republic Wireless, Simple Mobile, SpeedTalk Mobile, Straight Talk, Tello, TextNow, Ting Mobile, Tracfone, Ultra Mobile, UNREAL Mobile, US Mobile, Walmart Family Mobile and many more. Please check with your carrier directly for more information on their Bring Your Own Device program compatibility.