Blue: the blue lights indicate status related to connecting the reader to a device
Blinking blue light: The reader is ready to connect to a mobile device (but not yet connected)
Solid blue light: The reader has successfully connected to a mobile device.
Red: the red light indicates the status for readers after they are connected
Blinking red light: Indicates low battery. The reader will also blink red when it is plugged in and charging.
Solid red light: Reader charge is sufficient to take transactions