This app is only for WATTSTUNDE GmbH. Easy to use tool for monitoring your lithium battery! * The phone requires bluetooth4.0 with BLE (bluetooth low energy) functions. * Android 4.3 or later * Operating distance: <= 5m * The APP can only contact one battery at one time. * If you want to connect this battery with another mobile phone, pls leave this program from the first mobile phone. * The Android system is open on the platform. Not every smartphone manufacturer complies and some have customi