The PageFlip app allows you to reprogram the functionality of the pedal, monitor the battery level, and change settings such as the pedal Bluetooth name and auto-sleep time. For example, you can reprogram the pedal to emit a "Play/Pause", "VolumeUp", "Ctrl+Shift+S", or "F12" key instead of the preset keys provided with the default pedal modes. You should only reprogram your pedal if the app with which you use the pedal cannot interpret a default key like "Left/Up/Right/Down Arrow".
The features provided by this app only work for V14+ Firefly, V5+ Dragonfly, and V11+ Butterfly pedals. You can check the version number of your pedal on the label on the bottom of the pedal. The Butterfly pedal cannot be reprogrammed, and the app only includes support for monitoring its battery level.