How to trigger forward motion when I click Card board button/Magnet button?

I am developing content for Google Card board , The gyro for rotation is working. Here’s what is that I need expert’s advice on when I click the cardboard button/magnet I need the camera to start moving and when I click it again, I want it to stop…

For my app, I created a blueprint class with character as parent class and set it as the character class for the active game mode. In the blueprint I use the following setup

With my setup the character moves only in the plane. If the roll of the device is below 10° then it moves forward, when the device roll is above 10° the character strafes sideways. If you only need forward motion, the lower part handling the strafing is not needed.
The strafing is a little unintuitive and sometimes causes motion sickness. You should consider not using it.
Having the motion stop once you release the button is more intuitive in my opinion and you won’t get problems because people don’t know how to stop moving.

Hello I have a question, how do you detect magnetic clicker input?

I tried touch 1 but its not magnetic clicker.