Using the button

There is one button, and everything you can do with the sensor by hand goes through it.

Wake it up

A single short press. The light breathes to confirm.

Shut it down

Hold for two seconds until the light fades. This is a proper shutdown rather than sleep, so use it before travelling or storing the sensor for a while.

If it stops responding

Put the sensor on the charging dock for a few minutes and try the button again. Charging power alone will bring back a sensor that has run itself completely flat, which is by far the most common cause of a button that appears dead.