This App is only for TOPBAND Bluetooth LiFePO4 battery which base on bluetooth4.0 BLE technology. * The Best Utility tool for monitoring your lithium battery! * Event recorder and notification reminder, easily to manage the battery * The phone required bluetooth4.0 with BLE(bluetooth low energy) functions. * Android 4.3 or later * Measuring distance: <= 5m * Due to the bluetooth hardware feature, the APP only can connec with one battery every time. * If you want to connect this battery with an