A Bluetooth connection is required to start the FreeStyle Libre 2 sensor and to receive alarms through the app. Users do not need Bluetooth to scan their sensor. Bluetooth can be turned off and on as many times as users would like throughout the Sensor’s wear duration. If users decide to turn Bluetooth on after it has been turned off, they need to make sure that the sensor is near their phone, allowing their phone and sensor will automatically pair after a few minutes.