Hi @thomas6886, I assume you are referring to a means by which to turn off/on the eye tracker itself programatically? ie the functionality that is already present within the system tray icon of the Tobii Core Software?
I am afraid for the time being, this is not a feature we include in the Core SDK, although various workaround such as stopping the Tobii Windows Service via Powershell might serve your need. Apologies for any inconvenience.
If however, you intended something else, please let us know and we will try to assist.