For all versions of WHOOP, you cannot turn off your WHOOP device because it remains powered on as long as it is still charged.
NOTE: Your WHOOP will enter a low-power mode to conserve battery life if it is off the wrist and remains motionless.
How do I know if my WHOOP is in low-power mode?
You'll know your Strap is in low-power mode when the green light emitting diode (LED) on the bottom of the sensor turns off.
NOTE: Your WHOOP does not collect data when the green LED on the bottom of the sensor is off.