CHARGED TO LAST: With its high-powered 5,000 mAh polymer battery, the G1 can run longer than a day, even if you are using it for playing, calling, texting, videos and photos all at once. PERFORM BETTER: With Android Oreo (Go edition) Built with the latest operating system, the Android Oreo (Go edition) on the G1 provides you with a powerful user experience. The new and reimagined apps offer more storage, better performance, data safety and better security for your smartphone. DUAL LTE SIM SUPPORT: In addition to a powerful battery, the G1 also gives you more productivity with dual 4G SIM connectivity via two separate SD card slots. No need to separate your life into two phones- simply put in the two SIMs and enjoy LTE high-speed data for both, keeping you connected anytime, anywhere. EXPERIENCE MORE: With VoLTE/ViLTE The G1's advanced VoLTE/ViLTE technology enables you to make high-quality audio and video calls via your 4G networks at any time, any place, especially when network signals are bad. Simply call, connect and talk! PLEASE NOTE: The G1 is compatible with all GSM carriers such as T-Mobile, AT&T, and other carriers that operate on those networks. It does not work on CDMA networks such as VERIZON or SPRINT.