Cannot enter manual control mode in Kaya joystick example

I am following the tutorial of Kaya joystick application but cannot figure out how to enter manual control mode. Where I can find the left shoulder button in the following description?

“press and hold the left shoulder button to enter manual control mode, and then and use the left thumbstick to move the robot forward/backward and the right thumbstick to turn left/right.”

Hi Syone,

left shoulder is sometimes called left trigger. I hope this image helps:

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