Wireless remote control of all rear panel settings of the following loudspeakers:B12X / B15X and MPA200BTThe loudspeakers use Bluetooth 4 wireless technology to communicate with the app, so you will need a mobile device running Android 5 or higher.BEHRINGER LIVE CONTROL allows the user to:Remotely control input and output levels, plus EQ selectionRemotely control general speaker settings (including lock functionality)Update speaker firmware (notification on settings screen when connected to the Internet) In master / slave mode: - Adjust analog inputs individually per speaker or general Bluetooth wireless technology input level- Set balance for the speaker outputThe app does not play any sound. It is for remote control purposes only. Music level indicators are located above the input wheels.