Optimized UI design for any parties : With a simple and intuitive UI design, you will be able to control any functions very swiftly. Notice Depending on the audio model, some features may not be supported. May not operate smoothly, not be supported, or screen display problems may occur depending on your phone or the policy of telecom operators. Check the Bluetooth volume when using other Bluetooth devices after using the app and then use. Please update to the latest version to use.