One of the ways in which the Cinder Grill communicates is by lighting up the ring around the control knob in various colors. Here is a brief guide to those colors and their meanings: 

Off:         Idle mode (the Cinder Grill is not currently performing any task)

Solid blue:     Cooking under manual control.

Flashing blue:     Cooking under remote control via the App.

Yellow:     Calibrating the device

Green:     Calibration successful

Red:         Searing mode or error signal.