BlueSun and BlueBattery are Bluetooth Low Energy (BLE) based systems for recording the most important key figures of a motorhome's battery and/or solar system. A separate small device is connected to the battery circuit and to the existing solar charge controller. The BlueBattery app then displays all important parameters. BlueSun is a Bluetooth-based device for recording the most important key figures of a motorhome's solar system. In addition to the solar system, BlueBattery can also record