Built-in CC2541 Bluetooth 4.0 BLE module, supports iOS devices and Android 4.3 devices or later | A protective case is included to prevent dust and static electricity. | Free APP for Android , please search "DSD TECH Bluetooth" in google play. | Free APP for iOS devices(iPhone), please search "DSD TECH Bluetooth" in appstore. | DSD TECH provides a one-year warranty on this Bluetooth Relay. If you have any questions, please feel free to contact us.