There is certainly an application you can use with the SoundLink Max, but it's actually not mandatory. If you are doing use it, you'll get usage of EQing, speaker customization options, and firmware updates. Some are small plenty of to clip to your backpack, while others are more at https://www.bluetoothspeaker.top/dj-bluetooth-wireless-audio-player-sound-box-loudspeaker-rgb-speaker-bluetooth-speaker/