Mobiper 4K S4 Smartphone Android 4.2 MTK6589 Quad Core 1GB 4GB 5.0 Inch 12.0MP Camera white Mobiper 4K S4 Smartphone Android 4.2 MTK6589 Quad Core 1GB 4GB 5.0 Inch 12.0MP Camera white Free Tether - Use your 3G data service as a WiFi hot spot and connect your notebook, ipad or other device for free. No need to pay monthly tether fee 3G - 850/2100 bands. Fully compatible with at&t at 3.75G, compatilble with T-Mobile at 2G. For other network such as Straight Talk, Trac fone, Simple Mobile or Net 10 will require a manual APN setup Unlocked world GSM phone. 3G - 850/2100, 2G -850/900/1800/1900. Compatible with at&t, T-Mobile, Straight Talk, Simple Mobile and other GSM networks. Please make sure your SIM card is not locked with PUK code Unlocked cell phones are compatible with GSM carriers but are not compatible with CDMA Carriers.